path: root/src/coreclr/jit/compiler.h

// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

/*XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XX                                                                           XX
XX                           Compiler                                        XX
XX                                                                           XX
XX  Represents the method data we are currently JIT-compiling.               XX
XX  An instance of this class is created for every method we JIT.            XX
XX  This contains all the info needed for the method. So allocating a        XX
XX  a new instance per method makes it thread-safe.                          XX
XX  It should be used to do all the memory management for the compiler run.  XX
XX                                                                           XX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
*/

/*****************************************************************************/
#ifndef _COMPILER_H_
#define _COMPILER_H_
/*****************************************************************************/

#include "jit.h"
#include "opcode.h"
#include "varset.h"
#include "jitstd.h"
#include "jithashtable.h"
#include "gentree.h"
#include "debuginfo.h"
#include "lir.h"
#include "block.h"
#include "inline.h"
#include "jiteh.h"
#include "instr.h"
#include "regalloc.h"
#include "sm.h"
#include "cycletimer.h"
#include "blockset.h"
#include "arraystack.h"
#include "hashbv.h"
#include "jitexpandarray.h"
#include "tinyarray.h"
#include "valuenum.h"
#include "jittelemetry.h"
#include "namedintrinsiclist.h"
#ifdef LATE_DISASM
#include "disasm.h"
#endif

#include "codegeninterface.h"
#include "regset.h"
#include "jitgcinfo.h"

#if DUMP_GC_TABLES && defined(JIT32_GCENCODER)
#include "gcdump.h"
#endif

#include "emit.h"

// Forward declaration
template <class T>
inline var_types genActualType(T value);

#include "hwintrinsic.h"
#include "simd.h"
#include "simdashwintrinsic.h"

// This is only used locally in the JIT to indicate that
// a verification block should be inserted
#define SEH_VERIFICATION_EXCEPTION 0xe0564552 // VER

/*****************************************************************************
 *                  Forward declarations
 */

struct InfoHdr;              // defined in GCInfo.h
struct escapeMapping_t;      // defined in fgdiagnostic.cpp
class emitter;               // defined in emit.h
struct ShadowParamVarInfo;   // defined in GSChecks.cpp
struct InitVarDscInfo;       // defined in registerargconvention.h
class FgStack;               // defined in fgbasic.cpp
class Instrumentor;          // defined in fgprofile.cpp
class SpanningTreeVisitor;   // defined in fgprofile.cpp
class CSE_DataFlow;          // defined in OptCSE.cpp
class OptBoolsDsc;           // defined in optimizer.cpp
struct RelopImplicationInfo; // defined in redundantbranchopts.cpp
struct JumpThreadInfo;       // defined in redundantbranchopts.cpp
#ifdef DEBUG
struct IndentStack;
#endif

class Lowering; // defined in lower.h

// The following are defined in this file, Compiler.h

class Compiler;

/*****************************************************************************
 *                  Unwind info
 */

#include "unwind.h"

/*****************************************************************************/

//
// Declare global operator new overloads that use the compiler's arena allocator
//

void* operator new(size_t n, Compiler* context, CompMemKind cmk);
void* operator new[](size_t n, Compiler* context, CompMemKind cmk);

// Requires the definitions of "operator new" so including "LoopCloning.h" after the definitions.
#include "loopcloning.h"

/*****************************************************************************/

/* This is included here and not earlier as it needs the definition of "CSE"
 * which is defined in the section above */

/*****************************************************************************/

unsigned genLog2(unsigned value);
unsigned genLog2(unsigned __int64 value);

unsigned ReinterpretHexAsDecimal(unsigned in);

/*****************************************************************************/

const unsigned FLG_CCTOR = (CORINFO_FLG_CONSTRUCTOR | CORINFO_FLG_STATIC);

#ifdef DEBUG
const int BAD_STK_OFFS = 0xBAADF00D; // for LclVarDsc::lvStkOffs
#endif

//------------------------------------------------------------------------
// HFA info shared by LclVarDsc and CallArgABIInformation
//------------------------------------------------------------------------
inline bool IsHfa(CorInfoHFAElemType kind)
{
    return kind != CORINFO_HFA_ELEM_NONE;
}
inline var_types HfaTypeFromElemKind(CorInfoHFAElemType kind)
{
    switch (kind)
    {
        case CORINFO_HFA_ELEM_FLOAT:
            return TYP_FLOAT;
        case CORINFO_HFA_ELEM_DOUBLE:
            return TYP_DOUBLE;
#ifdef FEATURE_SIMD
        case CORINFO_HFA_ELEM_VECTOR64:
            return TYP_SIMD8;
        case CORINFO_HFA_ELEM_VECTOR128:
            return TYP_SIMD16;
#endif
        case CORINFO_HFA_ELEM_NONE:
            return TYP_UNDEF;
        default:
            assert(!"Invalid HfaElemKind");
            return TYP_UNDEF;
    }
}
inline CorInfoHFAElemType HfaElemKindFromType(var_types type)
{
    switch (type)
    {
        case TYP_FLOAT:
            return CORINFO_HFA_ELEM_FLOAT;
        case TYP_DOUBLE:
            return CORINFO_HFA_ELEM_DOUBLE;
#ifdef FEATURE_SIMD
        case TYP_SIMD8:
            return CORINFO_HFA_ELEM_VECTOR64;
        case TYP_SIMD16:
            return CORINFO_HFA_ELEM_VECTOR128;
#endif
        case TYP_UNDEF:
            return CORINFO_HFA_ELEM_NONE;
        default:
            assert(!"Invalid HFA Type");
            return CORINFO_HFA_ELEM_NONE;
    }
}

// The following holds the Local var info (scope information)
typedef const char* VarName; // Actual ASCII string
struct VarScopeDsc
{
    unsigned vsdVarNum; // (remapped) LclVarDsc number
    unsigned vsdLVnum;  // 'which' in eeGetLVinfo().
                        // Also, it is the index of this entry in the info.compVarScopes array,
                        // which is useful since the array is also accessed via the
                        // compEnterScopeList and compExitScopeList sorted arrays.

    IL_OFFSET vsdLifeBeg; // instr offset of beg of life
    IL_OFFSET vsdLifeEnd; // instr offset of end of life

#ifdef DEBUG
    VarName vsdName; // name of the var
#endif
};

// This class stores information associated with a LclVar SSA definition.
class LclSsaVarDsc
{
    // The basic block where the definition occurs. Definitions of uninitialized variables
    // are considered to occur at the start of the first basic block (fgFirstBB).
    //
    // TODO-Cleanup: In the case of uninitialized variables the block is set to nullptr by
    // SsaBuilder and changed to fgFirstBB during value numbering. It would be useful to
    // investigate and perhaps eliminate this rather unexpected behavior.
    BasicBlock* m_block = nullptr;
    // The GT_ASG node that generates the definition, or nullptr for definitions
    // of uninitialized variables.
    GenTreeOp* m_asg = nullptr;
    // The SSA number associated with the previous definition for partial (GTF_USEASG) defs.
    unsigned m_useDefSsaNum = SsaConfig::RESERVED_SSA_NUM;
    // Number of uses of this SSA def (may be an over-estimate).
    // May not be accurate for for promoted fields.
    unsigned short m_numUses = 0;
    // True if there may be phi args uses of this def
    // May not be accurate for for promoted fields.
    // (false implies all uses are non-phi).
    bool m_hasPhiUse = false;
    // True if there may be uses of the def in a different block.
    // May not be accurate for for promoted fields.
    bool m_hasGlobalUse = false;

public:
    LclSsaVarDsc()
    {
    }

    LclSsaVarDsc(BasicBlock* block) : m_block(block)
    {
    }

    LclSsaVarDsc(BasicBlock* block, GenTreeOp* asg) : m_block(block), m_asg(asg)
    {
        assert((asg == nullptr) || asg->OperIs(GT_ASG));
    }

    BasicBlock* GetBlock() const
    {
        return m_block;
    }

    void SetBlock(BasicBlock* block)
    {
        m_block = block;
    }

    GenTreeOp* GetAssignment() const
    {
        return m_asg;
    }

    void SetAssignment(GenTreeOp* asg)
    {
        assert((asg == nullptr) || asg->OperIs(GT_ASG));
        m_asg = asg;
    }

    unsigned GetUseDefSsaNum() const
    {
        return m_useDefSsaNum;
    }

    void SetUseDefSsaNum(unsigned ssaNum)
    {
        m_useDefSsaNum = ssaNum;
    }

    unsigned GetNumUses() const
    {
        return m_numUses;
    }

    void AddUse(BasicBlock* block)
    {
        if (block != m_block)
        {
            m_hasGlobalUse = true;
        }

        if (m_numUses < USHRT_MAX)
        {
            m_numUses++;
        }
    }

    void AddPhiUse(BasicBlock* block)
    {
        m_hasPhiUse = true;
        AddUse(block);
    }

    bool HasPhiUse() const
    {
        return m_hasPhiUse;
    }

    bool HasGlobalUse() const
    {
        return m_hasGlobalUse;
    }

    ValueNumPair m_vnPair;
};

// This class stores information associated with a memory SSA definition.
class SsaMemDef
{
public:
    ValueNumPair m_vnPair;
};

//------------------------------------------------------------------------
// SsaDefArray: A resizable array of SSA definitions.
//
// Unlike an ordinary resizable array implementation, this allows only element
// addition (by calling AllocSsaNum) and has special handling for RESERVED_SSA_NUM
// (basically it's a 1-based array). The array doesn't impose any particular
// requirements on the elements it stores and AllocSsaNum forwards its arguments
// to the array element constructor, this way the array supports both LclSsaVarDsc
// and SsaMemDef elements.
//
template <typename T>
class SsaDefArray
{
    T*       m_array;
    unsigned m_arraySize;
    unsigned m_count;

    static_assert_no_msg(SsaConfig::RESERVED_SSA_NUM == 0);
    static_assert_no_msg(SsaConfig::FIRST_SSA_NUM == 1);

    // Get the minimum valid SSA number.
    unsigned GetMinSsaNum() const
    {
        return SsaConfig::FIRST_SSA_NUM;
    }

    // Increase (double) the size of the array.
    void GrowArray(CompAllocator alloc)
    {
        unsigned oldSize = m_arraySize;
        unsigned newSize = max(2, oldSize * 2);

        T* newArray = alloc.allocate<T>(newSize);

        for (unsigned i = 0; i < oldSize; i++)
        {
            newArray[i] = m_array[i];
        }

        m_array     = newArray;
        m_arraySize = newSize;
    }

public:
    // Construct an empty SsaDefArray.
    SsaDefArray() : m_array(nullptr), m_arraySize(0), m_count(0)
    {
    }

    // Reset the array (used only if the SSA form is reconstructed).
    void Reset()
    {
        m_count = 0;
    }

    // Allocate a new SSA number (starting with SsaConfig::FIRST_SSA_NUM).
    template <class... Args>
    unsigned AllocSsaNum(CompAllocator alloc, Args&&... args)
    {
        if (m_count == m_arraySize)
        {
            GrowArray(alloc);
        }

        unsigned ssaNum    = GetMinSsaNum() + m_count;
        m_array[m_count++] = T(std::forward<Args>(args)...);

        // Ensure that the first SSA number we allocate is SsaConfig::FIRST_SSA_NUM
        assert((ssaNum == SsaConfig::FIRST_SSA_NUM) || (m_count > 1));

        return ssaNum;
    }

    // Get the number of SSA definitions in the array.
    unsigned GetCount() const
    {
        return m_count;
    }

    // Get a pointer to the SSA definition at the specified index.
    T* GetSsaDefByIndex(unsigned index) const
    {
        assert(index < m_count);
        return &m_array[index];
    }

    // Check if the specified SSA number is valid.
    bool IsValidSsaNum(unsigned ssaNum) const
    {
        return (GetMinSsaNum() <= ssaNum) && (ssaNum < (GetMinSsaNum() + m_count));
    }

    // Get a pointer to the SSA definition associated with the specified SSA number.
    T* GetSsaDef(unsigned ssaNum) const
    {
        assert(ssaNum != SsaConfig::RESERVED_SSA_NUM);
        return GetSsaDefByIndex(ssaNum - GetMinSsaNum());
    }

    // Get an SSA number associated with the specified SSA def (that must be in this array).
    unsigned GetSsaNum(T* ssaDef) const
    {
        assert((m_array <= ssaDef) && (ssaDef < &m_array[m_count]));
        return GetMinSsaNum() + static_cast<unsigned>(ssaDef - &m_array[0]);
    }
};

enum RefCountState
{
    RCS_INVALID, // not valid to get/set ref counts
    RCS_EARLY,   // early counts for struct promotion and struct passing
    RCS_NORMAL,  // normal ref counts (from lvaMarkRefs onward)
};

#ifdef DEBUG
// Reasons why we can't enregister a local.
enum class DoNotEnregisterReason
{
    None,
    AddrExposed,      // the address of this local is exposed.
    DontEnregStructs, // struct enregistration is disabled.
    NotRegSizeStruct, // the struct size does not much any register size, usually the struct size is too big.
    LocalField,       // the local is accessed with LCL_FLD, note we can do it not only for struct locals.
    VMNeedsStackAddr,
    LiveInOutOfHandler, // the local is alive in and out of exception handler and not single def.
    BlockOp,            // Is read or written via a block operation.
    IsStructArg,        // Is a struct passed as an argument in a way that requires a stack location.
    DepField,           // It is a field of a dependently promoted struct
    NoRegVars,          // opts.compFlags & CLFLG_REGVAR is not set
    MinOptsGC,          // It is a GC Ref and we are compiling MinOpts
#if !defined(TARGET_64BIT)
    LongParamField, // It is a decomposed field of a long parameter.
#endif
#ifdef JIT32_GCENCODER
    PinningRef,
#endif
    LclAddrNode, // the local is accessed with LCL_ADDR_VAR/FLD.
    CastTakesAddr,
    StoreBlkSrc,          // the local is used as STORE_BLK source.
    OneAsgRetyping,       // fgMorphOneAsgBlockOp prevents this local from being enregister.
    SwizzleArg,           // the local is passed using LCL_FLD as another type.
    BlockOpRet,           // the struct is returned and it promoted or there is a cast.
    ReturnSpCheck,        // the local is used to do SP check on return from function
    CallSpCheck,          // the local is used to do SP check on every call
    SimdUserForcesDep,    // a promoted struct was used by a SIMD/HWI node; it must be dependently promoted
    HiddenBufferStructArg // the argument is a hidden return buffer passed to a method.
};

enum class AddressExposedReason
{
    NONE,
    PARENT_EXPOSED,   // This is a promoted field but the parent is exposed.
    TOO_CONSERVATIVE, // Were marked as exposed to be conservative, fix these places.
    ESCAPE_ADDRESS,   // The address is escaping, for example, passed as call argument.
    WIDE_INDIR,       // We access via indirection with wider type.
    OSR_EXPOSED,      // It was exposed in the original method, osr has to repeat it.
    STRESS_LCL_FLD,   // Stress mode replaces localVar with localFld and makes them addrExposed.
    DISPATCH_RET_BUF  // Caller return buffer dispatch.
};

#endif // DEBUG

class LclVarDsc
{
public:
    // The constructor. Most things can just be zero'ed.
    //
    // Initialize the ArgRegs to REG_STK.
    // Morph will update if this local is passed in a register.
    LclVarDsc()
        : _lvArgReg(REG_STK)
        ,
#if FEATURE_MULTIREG_ARGS
        _lvOtherArgReg(REG_STK)
        ,
#endif // FEATURE_MULTIREG_ARGS
        lvClassHnd(NO_CLASS_HANDLE)
        , lvRefBlks(BlockSetOps::UninitVal())
        , lvPerSsaData()
    {
    }

    // note this only packs because var_types is a typedef of unsigned char
    var_types lvType : 5; // TYP_INT/LONG/FLOAT/DOUBLE/REF

    unsigned char lvIsParam : 1;           // is this a parameter?
    unsigned char lvIsRegArg : 1;          // is this an argument that was passed by register?
    unsigned char lvFramePointerBased : 1; // 0 = off of REG_SPBASE (e.g., ESP), 1 = off of REG_FPBASE (e.g., EBP)

    unsigned char lvOnFrame : 1;  // (part of) the variable lives on the frame
    unsigned char lvRegister : 1; // assigned to live in a register? For RyuJIT backend, this is only set if the
                                  // variable is in the same register for the entire function.
    unsigned char lvTracked : 1;  // is this a tracked variable?
    bool          lvTrackedNonStruct()
    {
        return lvTracked && lvType != TYP_STRUCT;
    }
    unsigned char lvPinned : 1; // is this a pinned variable?

    unsigned char lvMustInit : 1; // must be initialized

private:
    bool m_addrExposed : 1; // The address of this variable is "exposed" -- passed as an argument, stored in a
                            // global location, etc.
                            // We cannot reason reliably about the value of the variable.
public:
    unsigned char lvDoNotEnregister : 1; // Do not enregister this variable.
    unsigned char lvFieldAccessed : 1;   // The var is a struct local, and a field of the variable is accessed.  Affects
                                         // struct promotion.
    unsigned char lvLiveInOutOfHndlr : 1; // The variable is live in or out of an exception handler, and therefore must
                                          // be on the stack (at least at those boundaries.)

    unsigned char lvInSsa : 1;       // The variable is in SSA form (set by SsaBuilder)
    unsigned char lvIsCSE : 1;       // Indicates if this LclVar is a CSE variable.
    unsigned char lvHasLdAddrOp : 1; // has ldloca or ldarga opcode on this local.

    unsigned char lvHasILStoreOp : 1;         // there is at least one STLOC or STARG on this local
    unsigned char lvHasMultipleILStoreOp : 1; // there is more than one STLOC on this local

    unsigned char lvIsTemp : 1; // Short-lifetime compiler temp

#if FEATURE_IMPLICIT_BYREFS
    unsigned char lvIsImplicitByRef : 1; // Set if the argument is an implicit byref.
#endif                                   // FEATURE_IMPLICIT_BYREFS

#if defined(TARGET_LOONGARCH64)
    unsigned char lvIs4Field1 : 1; // Set if the 1st field is int or float within struct for LA-ABI64.
    unsigned char lvIs4Field2 : 1; // Set if the 2nd field is int or float within struct for LA-ABI64.
    unsigned char lvIsSplit : 1;   // Set if the argument is splited.
#endif                             // defined(TARGET_LOONGARCH64)

    unsigned char lvIsBoolean : 1; // set if variable is boolean
    unsigned char lvSingleDef : 1; // variable has a single def
                                   // before lvaMarkLocalVars: identifies ref type locals that can get type updates
                                   // after lvaMarkLocalVars: identifies locals that are suitable for optAddCopies

    unsigned char lvSingleDefRegCandidate : 1; // variable has a single def and hence is a register candidate
                                               // Currently, this is only used to decide if an EH variable can be
                                               // a register candidate or not.

    unsigned char lvDisqualifySingleDefRegCandidate : 1; // tracks variable that are disqualified from register
                                                         // candidancy

    unsigned char lvSpillAtSingleDef : 1; // variable has a single def (as determined by LSRA interval scan)
                                          // and is spilled making it candidate to spill right after the
                                          // first (and only) definition.
                                          // Note: We cannot reuse lvSingleDefRegCandidate because it is set
                                          // in earlier phase and the information might not be appropriate
                                          // in LSRA.

    unsigned char lvDisqualify : 1;   // variable is no longer OK for add copy optimization
    unsigned char lvVolatileHint : 1; // hint for AssertionProp

#ifndef TARGET_64BIT
    unsigned char lvStructDoubleAlign : 1; // Must we double align this struct?
#endif                                     // !TARGET_64BIT
#ifdef TARGET_64BIT
    unsigned char lvQuirkToLong : 1; // Quirk to allocate this LclVar as a 64-bit long
#endif
#ifdef DEBUG
    unsigned char lvKeepType : 1;       // Don't change the type of this variable
    unsigned char lvNoLclFldStress : 1; // Can't apply local field stress on this one
#endif
    unsigned char lvIsPtr : 1; // Might this be used in an address computation? (used by buffer overflow security
                               // checks)
    unsigned char lvIsUnsafeBuffer : 1; // Does this contain an unsafe buffer requiring buffer overflow security checks?
    unsigned char lvPromoted : 1; // True when this local is a promoted struct, a normed struct, or a "split" long on a
                                  // 32-bit target.  For implicit byref parameters, this gets hijacked between
                                  // fgRetypeImplicitByRefArgs and fgMarkDemotedImplicitByRefArgs to indicate whether
                                  // references to the arg are being rewritten as references to a promoted shadow local.
    unsigned char lvIsStructField : 1; // Is this local var a field of a promoted struct local?
    unsigned char lvContainsHoles : 1; // True when we have a promoted struct that contains holes
    unsigned char lvCustomLayout : 1;  // True when this struct has "CustomLayout"

    unsigned char lvIsMultiRegArg : 1; // true if this is a multireg LclVar struct used in an argument context
    unsigned char lvIsMultiRegRet : 1; // true if this is a multireg LclVar struct assigned from a multireg call

#ifdef DEBUG
    unsigned char lvHiddenBufferStructArg : 1; // True when this struct (or its field) are passed as hidden buffer
                                               // pointer.
#endif

#ifdef FEATURE_HFA_FIELDS_PRESENT
    CorInfoHFAElemType _lvHfaElemKind : 3; // What kind of an HFA this is (CORINFO_HFA_ELEM_NONE if it is not an HFA).
#endif                                     // FEATURE_HFA_FIELDS_PRESENT

#ifdef DEBUG
    // TODO-Cleanup: See the note on lvSize() - this flag is only in use by asserts that are checking for struct
    // types, and is needed because of cases where TYP_STRUCT is bashed to an integral type.
    // Consider cleaning this up so this workaround is not required.
    unsigned char lvUnusedStruct : 1; // All references to this promoted struct are through its field locals.
                                      // I.e. there is no longer any reference to the struct directly.
                                      // In this case we can simply remove this struct local.

    unsigned char lvUndoneStructPromotion : 1; // The struct promotion was undone and hence there should be no
                                               // reference to the fields of this struct.
#endif

    unsigned char lvLRACandidate : 1; // Tracked for linear scan register allocation purposes

#ifdef FEATURE_SIMD
    // Note that both SIMD vector args and locals are marked as lvSIMDType = true, but the
    // type of an arg node is TYP_BYREF and a local node is TYP_SIMD*.
    unsigned char lvSIMDType : 1;            // This is a SIMD struct
    unsigned char lvUsedInSIMDIntrinsic : 1; // This tells lclvar is used for simd intrinsic
    unsigned char lvSimdBaseJitType : 5;     // Note: this only packs because CorInfoType has less than 32 entries

    CorInfoType GetSimdBaseJitType() const
    {
        return (CorInfoType)lvSimdBaseJitType;
    }

    void SetSimdBaseJitType(CorInfoType simdBaseJitType)
    {
        assert(simdBaseJitType < (1 << 5));
        lvSimdBaseJitType = (unsigned char)simdBaseJitType;
    }

    var_types GetSimdBaseType() const;
#endif                             // FEATURE_SIMD
    unsigned char lvRegStruct : 1; // This is a reg-sized non-field-addressed struct.

    unsigned char lvClassIsExact : 1; // lvClassHandle is the exact type

#ifdef DEBUG
    unsigned char lvClassInfoUpdated : 1; // true if this var has updated class handle or exactness
#endif

    unsigned char lvImplicitlyReferenced : 1; // true if there are non-IR references to this local (prolog, epilog, gc,
                                              // eh)

    unsigned char lvSuppressedZeroInit : 1; // local needs zero init if we transform tail call to loop

    unsigned char lvHasExplicitInit : 1; // The local is explicitly initialized and doesn't need zero initialization in
                                         // the prolog. If the local has gc pointers, there are no gc-safe points
                                         // between the prolog and the explicit initialization.

    unsigned char lvIsOSRLocal : 1; // Root method local in an OSR method. Any stack home will be on the Tier0 frame.
                                    // Initial value will be defined by Tier0. Requires special handing in prolog.

    union {
        unsigned lvFieldLclStart; // The index of the local var representing the first field in the promoted struct
                                  // local.  For implicit byref parameters, this gets hijacked between
                                  // fgRetypeImplicitByRefArgs and fgMarkDemotedImplicitByRefArgs to point to the
                                  // struct local created to model the parameter's struct promotion, if any.
        unsigned lvParentLcl; // The index of the local var representing the parent (i.e. the promoted struct local).
                              // Valid on promoted struct local fields.
    };

    unsigned char lvFieldCnt; //  Number of fields in the promoted VarDsc.
    unsigned char lvFldOffset;
    unsigned char lvFldOrdinal;

#ifdef DEBUG
    unsigned char lvSingleDefDisqualifyReason = 'H';
#endif

    unsigned char lvAllDefsAreNoGc : 1; // For pinned locals: true if all defs of this local are no-gc

#if FEATURE_MULTIREG_ARGS
    regNumber lvRegNumForSlot(unsigned slotNum)
    {
        if (slotNum == 0)
        {
            return (regNumber)_lvArgReg;
        }
        else if (slotNum == 1)
        {
            return GetOtherArgReg();
        }
        else
        {
            assert(false && "Invalid slotNum!");
        }

        unreached();
    }
#endif // FEATURE_MULTIREG_ARGS

    CorInfoHFAElemType GetLvHfaElemKind() const
    {
#ifdef FEATURE_HFA_FIELDS_PRESENT
        return _lvHfaElemKind;
#else
        NOWAY_MSG("GetLvHfaElemKind");
        return CORINFO_HFA_ELEM_NONE;
#endif // FEATURE_HFA_FIELDS_PRESENT
    }

    void SetLvHfaElemKind(CorInfoHFAElemType elemKind)
    {
#ifdef FEATURE_HFA_FIELDS_PRESENT
        _lvHfaElemKind = elemKind;
#else
        NOWAY_MSG("SetLvHfaElemKind");
#endif // FEATURE_HFA_FIELDS_PRESENT
    }

    bool lvIsHfa() const
    {
        if (GlobalJitOptions::compFeatureHfa)
        {
            return IsHfa(GetLvHfaElemKind());
        }
        else
        {
            return false;
        }
    }

    bool lvIsHfaRegArg() const
    {
        if (GlobalJitOptions::compFeatureHfa)
        {
            return lvIsRegArg && lvIsHfa();
        }
        else
        {
            return false;
        }
    }

    //------------------------------------------------------------------------------
    // lvHfaSlots: Get the number of slots used by an HFA local
    //
    // Return Value:
    //    On Arm64 - Returns 1-4 indicating the number of register slots used by the HFA
    //    On Arm32 - Returns the total number of single FP register slots used by the HFA, max is 8
    //
    unsigned lvHfaSlots() const
    {
        assert(lvIsHfa());
        assert(varTypeIsStruct(lvType));
        unsigned slots = 0;
#ifdef TARGET_ARM
        slots = lvExactSize / sizeof(float);
        assert(slots <= 8);
#elif defined(TARGET_ARM64)
        switch (GetLvHfaElemKind())
        {
            case CORINFO_HFA_ELEM_NONE:
                assert(!"lvHfaSlots called for non-HFA");
                break;
            case CORINFO_HFA_ELEM_FLOAT:
                assert((lvExactSize % 4) == 0);
                slots = lvExactSize >> 2;
                break;
            case CORINFO_HFA_ELEM_DOUBLE:
            case CORINFO_HFA_ELEM_VECTOR64:
                assert((lvExactSize % 8) == 0);
                slots = lvExactSize >> 3;
                break;
            case CORINFO_HFA_ELEM_VECTOR128:
                assert((lvExactSize % 16) == 0);
                slots = lvExactSize >> 4;
                break;
            default:
                unreached();
        }
        assert(slots <= 4);
#endif //  TARGET_ARM64
        return slots;
    }

    // lvIsMultiRegArgOrRet()
    //     returns true if this is a multireg LclVar struct used in an argument context
    //               or if this is a multireg LclVar struct assigned from a multireg call
    bool lvIsMultiRegArgOrRet()
    {
        return lvIsMultiRegArg || lvIsMultiRegRet;
    }

#if defined(DEBUG)
private:
    DoNotEnregisterReason m_doNotEnregReason;

    AddressExposedReason m_addrExposedReason;

public:
    void SetDoNotEnregReason(DoNotEnregisterReason reason)
    {
        m_doNotEnregReason = reason;
    }

    DoNotEnregisterReason GetDoNotEnregReason() const
    {
        return m_doNotEnregReason;
    }

    AddressExposedReason GetAddrExposedReason() const
    {
        return m_addrExposedReason;
    }
#endif // DEBUG

public:
    void SetAddressExposed(bool value DEBUGARG(AddressExposedReason reason))
    {
        m_addrExposed = value;
        INDEBUG(m_addrExposedReason = reason);
    }

    void CleanAddressExposed()
    {
        m_addrExposed = false;
    }

    bool IsAddressExposed() const
    {
        return m_addrExposed;
    }

#ifdef DEBUG
    void SetHiddenBufferStructArg(char value)
    {
        lvHiddenBufferStructArg = value;
    }

    bool IsHiddenBufferStructArg() const
    {
        return lvHiddenBufferStructArg;
    }
#endif

private:
    regNumberSmall _lvRegNum; // Used to store the register this variable is in (or, the low register of a
                              // register pair). It is set during codegen any time the
                              // variable is enregistered (lvRegister is only set
                              // to non-zero if the variable gets the same register assignment for its entire
                              // lifetime).
#if !defined(TARGET_64BIT)
    regNumberSmall _lvOtherReg; // Used for "upper half" of long var.
#endif                          // !defined(TARGET_64BIT)

    regNumberSmall _lvArgReg; // The (first) register in which this argument is passed.

#if FEATURE_MULTIREG_ARGS
    regNumberSmall _lvOtherArgReg; // Used for the second part of the struct passed in a register.
                                   // Note this is defined but not used by ARM32
#endif                             // FEATURE_MULTIREG_ARGS

    regNumberSmall _lvArgInitReg; // the register into which the argument is moved at entry

public:
    // The register number is stored in a small format (8 bits), but the getters return and the setters take
    // a full-size (unsigned) format, to localize the casts here.

    /////////////////////

    regNumber GetRegNum() const
    {
        return (regNumber)_lvRegNum;
    }

    void SetRegNum(regNumber reg)
    {
        _lvRegNum = (regNumberSmall)reg;
        assert(_lvRegNum == reg);
    }

/////////////////////

#if defined(TARGET_64BIT)

    regNumber GetOtherReg() const
    {
        assert(!"shouldn't get here"); // can't use "unreached();" because it's NORETURN, which causes C4072
                                       // "unreachable code" warnings
        return REG_NA;
    }

    void SetOtherReg(regNumber reg)
    {
        assert(!"shouldn't get here"); // can't use "unreached();" because it's NORETURN, which causes C4072
                                       // "unreachable code" warnings
    }
#else  // !TARGET_64BIT

    regNumber GetOtherReg() const
    {
        return (regNumber)_lvOtherReg;
    }

    void SetOtherReg(regNumber reg)
    {
        _lvOtherReg = (regNumberSmall)reg;
        assert(_lvOtherReg == reg);
    }
#endif // !TARGET_64BIT

    /////////////////////

    regNumber GetArgReg() const
    {
        return (regNumber)_lvArgReg;
    }

    void SetArgReg(regNumber reg)
    {
        _lvArgReg = (regNumberSmall)reg;
        assert(_lvArgReg == reg);
    }

#if FEATURE_MULTIREG_ARGS

    regNumber GetOtherArgReg() const
    {
        return (regNumber)_lvOtherArgReg;
    }

    void SetOtherArgReg(regNumber reg)
    {
        _lvOtherArgReg = (regNumberSmall)reg;
        assert(_lvOtherArgReg == reg);
    }
#endif // FEATURE_MULTIREG_ARGS

#ifdef FEATURE_SIMD
    // Is this is a SIMD struct?
    bool lvIsSIMDType() const
    {
        return lvSIMDType;
    }

    // Is this is a SIMD struct which is used for SIMD intrinsic?
    bool lvIsUsedInSIMDIntrinsic() const
    {
        return lvUsedInSIMDIntrinsic;
    }
#else
    // If feature_simd not enabled, return false
    bool lvIsSIMDType() const
    {
        return false;
    }
    bool lvIsUsedInSIMDIntrinsic() const
    {
        return false;
    }
#endif

    /////////////////////

    regNumber GetArgInitReg() const
    {
        return (regNumber)_lvArgInitReg;
    }

    void SetArgInitReg(regNumber reg)
    {
        _lvArgInitReg = (regNumberSmall)reg;
        assert(_lvArgInitReg == reg);
    }

    /////////////////////

    bool lvIsRegCandidate() const
    {
        return lvLRACandidate != 0;
    }

    bool lvIsInReg() const
    {
        return lvIsRegCandidate() && (GetRegNum() != REG_STK);
    }

    regMaskTP lvRegMask() const
    {
        regMaskTP regMask = RBM_NONE;
        if (varTypeUsesFloatReg(TypeGet()))
        {
            if (GetRegNum() != REG_STK)
            {
                regMask = genRegMaskFloat(GetRegNum(), TypeGet());
            }
        }
        else
        {
            if (GetRegNum() != REG_STK)
            {
                regMask = genRegMask(GetRegNum());
            }
        }
        return regMask;
    }

    unsigned short lvVarIndex; // variable tracking index

private:
    unsigned short m_lvRefCnt; // unweighted (real) reference count.  For implicit by reference
                               // parameters, this gets hijacked from fgResetImplicitByRefRefCount
                               // through fgMarkDemotedImplicitByRefArgs, to provide a static
                               // appearance count (computed during address-exposed analysis)
                               // that fgMakeOutgoingStructArgCopy consults during global morph
                               // to determine if eliding its copy is legal.

    weight_t m_lvRefCntWtd; // weighted reference count

public:
    unsigned short lvRefCnt(RefCountState state = RCS_NORMAL) const;
    void incLvRefCnt(unsigned short delta, RefCountState state = RCS_NORMAL);
    void setLvRefCnt(unsigned short newValue, RefCountState state = RCS_NORMAL);

    weight_t lvRefCntWtd(RefCountState state = RCS_NORMAL) const;
    void incLvRefCntWtd(weight_t delta, RefCountState state = RCS_NORMAL);
    void setLvRefCntWtd(weight_t newValue, RefCountState state = RCS_NORMAL);

private:
    int lvStkOffs; // stack offset of home in bytes.

public:
    int GetStackOffset() const
    {
        return lvStkOffs;
    }

    void SetStackOffset(int offset)
    {
        lvStkOffs = offset;
    }

    unsigned lvExactSize; // (exact) size of a STRUCT/SIMD/BLK local in bytes.

    unsigned lvSize() const;

    size_t lvArgStackSize() const;

    unsigned lvSlotNum; // original slot # (if remapped)

    // class handle for the local or null if not known or not a class,
    // for a struct handle use `GetStructHnd()`.
    CORINFO_CLASS_HANDLE lvClassHnd;

    // Get class handle for a struct local or implicitByRef struct local.
    CORINFO_CLASS_HANDLE GetStructHnd() const
    {
#ifdef FEATURE_SIMD
        if (lvSIMDType && (m_layout == nullptr))
        {
            return NO_CLASS_HANDLE;
        }
#endif

        CORINFO_CLASS_HANDLE structHnd = GetLayout()->GetClassHandle();
        assert(structHnd != NO_CLASS_HANDLE);
        return structHnd;
    }

private:
    ClassLayout* m_layout; // layout info for structs

public:
    BlockSet   lvRefBlks;          // Set of blocks that contain refs
    Statement* lvDefStmt;          // Pointer to the statement with the single definition
    void       lvaDisqualifyVar(); // Call to disqualify a local variable from use in optAddCopies

    var_types TypeGet() const
    {
        return (var_types)lvType;
    }
    bool lvStackAligned() const
    {
        assert(lvIsStructField);
        return ((lvFldOffset % TARGET_POINTER_SIZE) == 0);
    }
    bool lvNormalizeOnLoad() const
    {
        return varTypeIsSmall(TypeGet()) &&
               // lvIsStructField is treated the same as the aliased local, see fgDoNormalizeOnStore.
               (lvIsParam || m_addrExposed || lvIsStructField);
    }

    bool lvNormalizeOnStore() const
    {
        return varTypeIsSmall(TypeGet()) &&
               // lvIsStructField is treated the same as the aliased local, see fgDoNormalizeOnStore.
               !(lvIsParam || m_addrExposed || lvIsStructField);
    }

    void incRefCnts(weight_t weight, Compiler* pComp, RefCountState state = RCS_NORMAL, bool propagate = true);

    var_types GetHfaType() const
    {
        if (GlobalJitOptions::compFeatureHfa)
        {
            assert(lvIsHfa());
            return HfaTypeFromElemKind(GetLvHfaElemKind());
        }
        else
        {
            return TYP_UNDEF;
        }
    }

    void SetHfaType(var_types type)
    {
        if (GlobalJitOptions::compFeatureHfa)
        {
            CorInfoHFAElemType elemKind = HfaElemKindFromType(type);
            SetLvHfaElemKind(elemKind);
            // Ensure we've allocated enough bits.
            assert(GetLvHfaElemKind() == elemKind);
        }
    }

    // Returns true if this variable contains GC pointers (including being a GC pointer itself).
    bool HasGCPtr() const
    {
        return varTypeIsGC(lvType) || ((lvType == TYP_STRUCT) && m_layout->HasGCPtr());
    }

    // Returns the layout of a struct variable or implicit byref.
    ClassLayout* GetLayout() const
    {
#if FEATURE_IMPLICIT_BYREFS
        assert(varTypeIsStruct(TypeGet()) || (lvIsImplicitByRef && (TypeGet() == TYP_BYREF)));
#else
        assert(varTypeIsStruct(TypeGet()));
#endif
        return m_layout;
    }

    // Sets the layout of a struct variable.
    void SetLayout(ClassLayout* layout)
    {
        assert(varTypeIsStruct(lvType));
        assert((m_layout == nullptr) || ClassLayout::AreCompatible(m_layout, layout));
        m_layout = layout;
    }

    SsaDefArray<LclSsaVarDsc> lvPerSsaData;

    // Returns the address of the per-Ssa data for the given ssaNum (which is required
    // not to be the SsaConfig::RESERVED_SSA_NUM, which indicates that the variable is
    // not an SSA variable).
    LclSsaVarDsc* GetPerSsaData(unsigned ssaNum) const
    {
        return lvPerSsaData.GetSsaDef(ssaNum);
    }

    // Returns the SSA number for "ssaDef". Requires "ssaDef" to be a valid definition
    // of this variable.
    unsigned GetSsaNumForSsaDef(LclSsaVarDsc* ssaDef)
    {
        return lvPerSsaData.GetSsaNum(ssaDef);
    }

    var_types GetRegisterType(const GenTreeLclVarCommon* tree) const;

    var_types GetRegisterType() const;

    var_types GetStackSlotHomeType() const;

    bool IsEnregisterableType() const
    {
        return GetRegisterType() != TYP_UNDEF;
    }

    bool IsEnregisterableLcl() const
    {
        if (lvDoNotEnregister)
        {
            return false;
        }
        return IsEnregisterableType();
    }

    //-----------------------------------------------------------------------------
    //  IsAlwaysAliveInMemory: Determines if this variable's value is always
    //     up-to-date on stack. This is possible if this is an EH-var or
    //     we decided to spill after single-def.
    //
    bool IsAlwaysAliveInMemory() const
    {
        return lvLiveInOutOfHndlr || lvSpillAtSingleDef;
    }

    bool CanBeReplacedWithItsField(Compiler* comp) const;

#ifdef DEBUG
public:
    const char* lvReason;

    void PrintVarReg() const
    {
        printf("%s", getRegName(GetRegNum()));
    }
#endif // DEBUG

}; // class LclVarDsc

enum class SymbolicIntegerValue : int32_t
{
    LongMin,
    IntMin,
    ShortMin,
    ByteMin,
    Zero,
    One,
    ByteMax,
    UByteMax,
    ShortMax,
    UShortMax,
    ArrayLenMax,
    IntMax,
    UIntMax,
    LongMax,
};

inline constexpr bool operator>(SymbolicIntegerValue left, SymbolicIntegerValue right)
{
    return static_cast<int32_t>(left) > static_cast<int32_t>(right);
}

inline constexpr bool operator>=(SymbolicIntegerValue left, SymbolicIntegerValue right)
{
    return static_cast<int32_t>(left) >= static_cast<int32_t>(right);
}

inline constexpr bool operator<(SymbolicIntegerValue left, SymbolicIntegerValue right)
{
    return static_cast<int32_t>(left) < static_cast<int32_t>(right);
}

inline constexpr bool operator<=(SymbolicIntegerValue left, SymbolicIntegerValue right)
{
    return static_cast<int32_t>(left) <= static_cast<int32_t>(right);
}

// Represents an integral range useful for reasoning about integral casts.
// It uses a symbolic representation for lower and upper bounds so
// that it can efficiently handle integers of all sizes on all hosts.
//
// Note that the ranges represented by this class are **always** in the
// "signed" domain. This is so that if we know the range a node produces, it
// can be trivially used to determine if a cast above the node does or does not
// overflow, which requires that the interpretation of integers be the same both
// for the "input" and "output". We choose signed interpretation here because it
// produces nice continuous ranges and because IR uses sign-extension for constants.
//
// Some examples of how ranges are computed for casts:
// 1. CAST_OVF(ubyte <- uint): does not overflow for [0..UBYTE_MAX], produces the
//    same range - all casts that do not change the representation, i. e. have the same
//    "actual" input and output type, have the same "input" and "output" range.
// 2. CAST_OVF(ulong <- uint): never overflows => the "input" range is [INT_MIN..INT_MAX]
//    (aka all possible 32 bit integers). Produces [0..UINT_MAX] (aka all possible 32
//    bit integers zero-extended to 64 bits).
// 3. CAST_OVF(int <- uint): overflows for inputs larger than INT_MAX <=> less than 0
//    when interpreting as signed => the "input" range is [0..INT_MAX], the same range
//    being the produced one as the node does not change the width of the integer.
//
class IntegralRange
{
private:
    SymbolicIntegerValue m_lowerBound;
    SymbolicIntegerValue m_upperBound;

public:
    IntegralRange() = default;

    IntegralRange(SymbolicIntegerValue lowerBound, SymbolicIntegerValue upperBound)
        : m_lowerBound(lowerBound), m_upperBound(upperBound)
    {
        assert(lowerBound <= upperBound);
    }

    SymbolicIntegerValue GetLowerBound()
    {
        return m_lowerBound;
    }

    SymbolicIntegerValue GetUpperBound()
    {
        return m_upperBound;
    }

    bool Contains(int64_t value) const;

    bool Contains(IntegralRange other) const
    {
        return (m_lowerBound <= other.m_lowerBound) && (other.m_upperBound <= m_upperBound);
    }

    bool IsPositive()
    {
        return m_lowerBound >= SymbolicIntegerValue::Zero;
    }

    bool Equals(IntegralRange other) const
    {
        return (m_lowerBound == other.m_lowerBound) && (m_upperBound == other.m_upperBound);
    }

    static int64_t SymbolicToRealValue(SymbolicIntegerValue value);
    static SymbolicIntegerValue LowerBoundForType(var_types type);
    static SymbolicIntegerValue UpperBoundForType(var_types type);

    static IntegralRange ForType(var_types type)
    {
        return {LowerBoundForType(type), UpperBoundForType(type)};
    }

    static IntegralRange ForNode(GenTree* node, Compiler* compiler);
    static IntegralRange ForCastInput(GenTreeCast* cast);
    static IntegralRange ForCastOutput(GenTreeCast* cast);
    static IntegralRange Union(IntegralRange range1, IntegralRange range2);

#ifdef DEBUG
    static void Print(IntegralRange range);
#endif // DEBUG
};

/*
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XX                                                                           XX
XX                           TempsInfo                                       XX
XX                                                                           XX
XX  The temporary lclVars allocated by the compiler for code generation      XX
XX                                                                           XX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
*/

/*****************************************************************************
 *
 *  The following keeps track of temporaries allocated in the stack frame
 *  during code-generation (after register allocation). These spill-temps are
 *  only used if we run out of registers while evaluating a tree.
 *
 *  These are different from the more common temps allocated by lvaGrabTemp().
 */

class TempDsc
{
public:
    TempDsc* tdNext;

private:
    int tdOffs;
#ifdef DEBUG
    static const int BAD_TEMP_OFFSET = 0xDDDDDDDD; // used as a sentinel "bad value" for tdOffs in DEBUG
#endif                                             // DEBUG

    int       tdNum;
    BYTE      tdSize;
    var_types tdType;

public:
    TempDsc(int _tdNum, unsigned _tdSize, var_types _tdType) : tdNum(_tdNum), tdSize((BYTE)_tdSize), tdType(_tdType)
    {
#ifdef DEBUG
        // temps must have a negative number (so they have a different number from all local variables)
        assert(tdNum < 0);
        tdOffs = BAD_TEMP_OFFSET;
#endif // DEBUG
        if (tdNum != _tdNum)
        {
            IMPL_LIMITATION("too many spill temps");
        }
    }

#ifdef DEBUG
    bool tdLegalOffset() const
    {
        return tdOffs != BAD_TEMP_OFFSET;
    }
#endif // DEBUG

    int tdTempOffs() const
    {
        assert(tdLegalOffset());
        return tdOffs;
    }
    void tdSetTempOffs(int offs)
    {
        tdOffs = offs;
        assert(tdLegalOffset());
    }
    void tdAdjustTempOffs(int offs)
    {
        tdOffs += offs;
        assert(tdLegalOffset());
    }

    int tdTempNum() const
    {
        assert(tdNum < 0);
        return tdNum;
    }
    unsigned tdTempSize() const
    {
        return tdSize;
    }
    var_types tdTempType() const
    {
        return tdType;
    }
};

// Specify compiler data that a phase might modify
enum class PhaseStatus : unsigned
{
    MODIFIED_NOTHING,    // Phase did not make any changes that warrant running post-phase checks or dumping
                         // the main jit data strutures.
    MODIFIED_EVERYTHING, // Phase made changes that warrant running post-phase checks or dumping
                         // the main jit data strutures.
};

// interface to hide linearscan implementation from rest of compiler
class LinearScanInterface
{
public:
    virtual PhaseStatus doLinearScan()                         = 0;
    virtual void recordVarLocationsAtStartOfBB(BasicBlock* bb) = 0;
    virtual bool willEnregisterLocalVars() const               = 0;
#if TRACK_LSRA_STATS
    virtual void dumpLsraStatsCsv(FILE* file)     = 0;
    virtual void dumpLsraStatsSummary(FILE* file) = 0;
#endif // TRACK_LSRA_STATS
};

LinearScanInterface* getLinearScanAllocator(Compiler* comp);

// This enumeration names the phases into which we divide compilation.  The phases should completely
// partition a compilation.
enum Phases
{
#define CompPhaseNameMacro(enum_nm, string_nm, hasChildren, parent, measureIR) enum_nm,
#include "compphases.h"
    PHASE_NUMBER_OF
};

extern const char* PhaseNames[];
extern const char* PhaseEnums[];

// Specify which checks should be run after each phase
//
enum class PhaseChecks
{
    CHECK_NONE,
    CHECK_ALL
};

// Specify which dumps should be run after each phase
//
enum class PhaseDumps
{
    DUMP_NONE,
    DUMP_ALL
};

// The following enum provides a simple 1:1 mapping to CLR API's
enum API_ICorJitInfo_Names
{
#define DEF_CLR_API(name) API_##name,
#include "ICorJitInfo_names_generated.h"
    API_COUNT
};

//---------------------------------------------------------------
// Compilation time.
//

// A "CompTimeInfo" is a structure for tracking the compilation time of one or more methods.
// We divide a compilation into a sequence of contiguous phases, and track the total (per-thread) cycles
// of the compilation, as well as the cycles for each phase.  We also track the number of bytecodes.
// If there is a failure in reading a timer at any point, the "CompTimeInfo" becomes invalid, as indicated
// by "m_timerFailure" being true.
// If FEATURE_JIT_METHOD_PERF is not set, we define a minimal form of this, enough to let other code compile.
struct CompTimeInfo
{
#ifdef FEATURE_JIT_METHOD_PERF
    // The string names of the phases.
    static const char* PhaseNames[];

    static bool PhaseHasChildren[];
    static int  PhaseParent[];
    static bool PhaseReportsIRSize[];

    unsigned         m_byteCodeBytes;
    unsigned __int64 m_totalCycles;
    unsigned __int64 m_invokesByPhase[PHASE_NUMBER_OF];
    unsigned __int64 m_cyclesByPhase[PHASE_NUMBER_OF];
#if MEASURE_CLRAPI_CALLS
    unsigned __int64 m_CLRinvokesByPhase[PHASE_NUMBER_OF];
    unsigned __int64 m_CLRcyclesByPhase[PHASE_NUMBER_OF];
#endif

    unsigned m_nodeCountAfterPhase[PHASE_NUMBER_OF];

    // For better documentation, we call EndPhase on
    // non-leaf phases.  We should also call EndPhase on the
    // last leaf subphase; obviously, the elapsed cycles between the EndPhase
    // for the last leaf subphase and the EndPhase for an ancestor should be very small.
    // We add all such "redundant end phase" intervals to this variable below; we print
    // it out in a report, so we can verify that it is, indeed, very small.  If it ever
    // isn't, this means that we're doing something significant between the end of the last
    // declared subphase and the end of its parent.
    unsigned __int64 m_parentPhaseEndSlop;
    bool             m_timerFailure;

#if MEASURE_CLRAPI_CALLS
    // The following measures the time spent inside each individual CLR API call.
    unsigned         m_allClrAPIcalls;
    unsigned         m_perClrAPIcalls[API_ICorJitInfo_Names::API_COUNT];
    unsigned __int64 m_allClrAPIcycles;
    unsigned __int64 m_perClrAPIcycles[API_ICorJitInfo_Names::API_COUNT];
    unsigned __int32 m_maxClrAPIcycles[API_ICorJitInfo_Names::API_COUNT];
#endif // MEASURE_CLRAPI_CALLS

    CompTimeInfo(unsigned byteCodeBytes);
#endif
};

#ifdef FEATURE_JIT_METHOD_PERF

#if MEASURE_CLRAPI_CALLS
struct WrapICorJitInfo;
#endif

// This class summarizes the JIT time information over the course of a run: the number of methods compiled,
// and the total and maximum timings.  (These are instances of the "CompTimeInfo" type described above).
// The operation of adding a single method's timing to the summary may be performed concurrently by several
// threads, so it is protected by a lock.
// This class is intended to be used as a singleton type, with only a single instance.
class CompTimeSummaryInfo
{
    // This lock protects the fields of all CompTimeSummaryInfo(s) (of which we expect there to be one).
    static CritSecObject s_compTimeSummaryLock;

    int          m_numMethods;
    int          m_totMethods;
    CompTimeInfo m_total;
    CompTimeInfo m_maximum;

    int          m_numFilteredMethods;
    CompTimeInfo m_filtered;

    // This can use what ever data you want to determine if the value to be added
    // belongs in the filtered section (it's always included in the unfiltered section)
    bool IncludedInFilteredData(CompTimeInfo& info);

public:
    // This is the unique CompTimeSummaryInfo object for this instance of the runtime.
    static CompTimeSummaryInfo s_compTimeSummary;

    CompTimeSummaryInfo()
        : m_numMethods(0), m_totMethods(0), m_total(0), m_maximum(0), m_numFilteredMethods(0), m_filtered(0)
    {
    }

    // Assumes that "info" is a completed CompTimeInfo for a compilation; adds it to the summary.
    // This is thread safe.
    void AddInfo(CompTimeInfo& info, bool includePhases);

    // Print the summary information to "f".
    // This is not thread-safe; assumed to be called by only one thread.
    void Print(FILE* f);
};

// A JitTimer encapsulates a CompTimeInfo for a single compilation. It also tracks the start of compilation,
// and when the current phase started.  This is intended to be part of a Compilation object.
//
class JitTimer
{
    unsigned __int64 m_start;         // Start of the compilation.
    unsigned __int64 m_curPhaseStart; // Start of the current phase.
#if MEASURE_CLRAPI_CALLS
    unsigned __int64 m_CLRcallStart;   // Start of the current CLR API call (if any).
    unsigned __int64 m_CLRcallInvokes; // CLR API invokes under current outer so far
    unsigned __int64 m_CLRcallCycles;  // CLR API  cycles under current outer so far.
    int              m_CLRcallAPInum;  // The enum/index of the current CLR API call (or -1).
    static double    s_cyclesPerSec;   // Cached for speedier measurements
#endif
#ifdef DEBUG
    Phases m_lastPhase; // The last phase that was completed (or (Phases)-1 to start).
#endif
    CompTimeInfo m_info; // The CompTimeInfo for this compilation.

    static CritSecObject s_csvLock; // Lock to protect the time log file.
    static FILE*         s_csvFile; // The time log file handle.
    void PrintCsvMethodStats(Compiler* comp);

private:
    void* operator new(size_t);
    void* operator new[](size_t);
    void operator delete(void*);
    void operator delete[](void*);

public:
    // Initialized the timer instance
    JitTimer(unsigned byteCodeSize);

    static JitTimer* Create(Compiler* comp, unsigned byteCodeSize)
    {
        return ::new (comp, CMK_Unknown) JitTimer(byteCodeSize);
    }

    static void PrintCsvHeader();

    // Ends the current phase (argument is for a redundant check).
    void EndPhase(Compiler* compiler, Phases phase);

#if MEASURE_CLRAPI_CALLS
    // Start and end a timed CLR API call.
    void CLRApiCallEnter(unsigned apix);
    void CLRApiCallLeave(unsigned apix);
#endif // MEASURE_CLRAPI_CALLS

    // Completes the timing of the current method, which is assumed to have "byteCodeBytes" bytes of bytecode,
    // and adds it to "sum".
    void Terminate(Compiler* comp, CompTimeSummaryInfo& sum, bool includePhases);

    // Attempts to query the cycle counter of the current thread.  If successful, returns "true" and sets
    // *cycles to the cycle counter value.  Otherwise, returns false and sets the "m_timerFailure" flag of
    // "m_info" to true.
    bool GetThreadCycles(unsigned __int64* cycles)
    {
        bool res = CycleTimer::GetThreadCyclesS(cycles);
        if (!res)
        {
            m_info.m_timerFailure = true;
        }
        return res;
    }

    static void Shutdown();
};
#endif // FEATURE_JIT_METHOD_PERF

//------------------- Function/Funclet info -------------------------------
enum FuncKind : BYTE
{
    FUNC_ROOT,    // The main/root function (always id==0)
    FUNC_HANDLER, // a funclet associated with an EH handler (finally, fault, catch, filter handler)
    FUNC_FILTER,  // a funclet associated with an EH filter
    FUNC_COUNT
};

class emitLocation;

struct FuncInfoDsc
{
    FuncKind       funKind;
    BYTE           funFlags;   // Currently unused, just here for padding
    unsigned short funEHIndex; // index, into the ebd table, of innermost EH clause corresponding to this
                               // funclet. It is only valid if funKind field indicates this is a
                               // EH-related funclet: FUNC_HANDLER or FUNC_FILTER

#if defined(TARGET_AMD64)

    // TODO-AMD64-Throughput: make the AMD64 info more like the ARM info to avoid having this large static array.
    emitLocation* startLoc;
    emitLocation* endLoc;
    emitLocation* coldStartLoc; // locations for the cold section, if there is one.
    emitLocation* coldEndLoc;
    UNWIND_INFO   unwindHeader;
    // Maximum of 255 UNWIND_CODE 'nodes' and then the unwind header. If there are an odd
    // number of codes, the VM or Zapper will 4-byte align the whole thing.
    BYTE     unwindCodes[offsetof(UNWIND_INFO, UnwindCode) + (0xFF * sizeof(UNWIND_CODE))];
    unsigned unwindCodeSlot;

#elif defined(TARGET_X86)

    emitLocation* startLoc;
    emitLocation* endLoc;
    emitLocation* coldStartLoc; // locations for the cold section, if there is one.
    emitLocation* coldEndLoc;

#elif defined(TARGET_ARMARCH) || defined(TARGET_LOONGARCH64)

    UnwindInfo  uwi;     // Unwind information for this function/funclet's hot  section
    UnwindInfo* uwiCold; // Unwind information for this function/funclet's cold section
                         //   Note: we only have a pointer here instead of the actual object,
                         //   to save memory in the JIT case (compared to the NGEN case),
                         //   where we don't have any cold section.
                         //   Note 2: we currently don't support hot/cold splitting in functions
                         //   with EH, so uwiCold will be NULL for all funclets.

    emitLocation* startLoc;
    emitLocation* endLoc;
    emitLocation* coldStartLoc; // locations for the cold section, if there is one.
    emitLocation* coldEndLoc;

#endif // TARGET_ARMARCH || TARGET_LOONGARCH64

#if defined(FEATURE_CFI_SUPPORT)
    jitstd::vector<CFI_CODE>* cfiCodes;
#endif // FEATURE_CFI_SUPPORT

    // Eventually we may want to move rsModifiedRegsMask, lvaOutgoingArgSize, and anything else
    // that isn't shared between the main function body and funclets.
};

struct TempInfo
{
    GenTree* asg;
    GenTree* load;
};

#ifdef DEBUG
// XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
// We have the ability to mark source expressions with "Test Labels."
// These drive assertions within the JIT, or internal JIT testing.  For example, we could label expressions
// that should be CSE defs, and other expressions that should uses of those defs, with a shared label.

enum TestLabel // This must be kept identical to System.Runtime.CompilerServices.JitTestLabel.TestLabel.
{
    TL_SsaName,
    TL_VN,        // Defines a "VN equivalence class".  (For full VN, including exceptions thrown).
    TL_VNNorm,    // Like above, but uses the non-exceptional value of the expression.
    TL_CSE_Def,   //  This must be identified in the JIT as a CSE def
    TL_CSE_Use,   //  This must be identified in the JIT as a CSE use
    TL_LoopHoist, // Expression must (or must not) be hoisted out of the loop.
};

struct TestLabelAndNum
{
    TestLabel m_tl;
    ssize_t   m_num;

    TestLabelAndNum() : m_tl(TestLabel(0)), m_num(0)
    {
    }
};

typedef JitHashTable<GenTree*, JitPtrKeyFuncs<GenTree>, TestLabelAndNum> NodeToTestDataMap;

// XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
#endif // DEBUG

//-------------------------------------------------------------------------
// LoopFlags: flags for the loop table.
//
enum LoopFlags : unsigned short
{
    LPFLG_EMPTY = 0,

    // LPFLG_UNUSED  = 0x0001,
    // LPFLG_UNUSED  = 0x0002,
    LPFLG_ITER = 0x0004, // loop of form: for (i = icon or expression; test_condition(); i++)
    // LPFLG_UNUSED    = 0x0008,

    LPFLG_CONTAINS_CALL = 0x0010, // If executing the loop body *may* execute a call
    // LPFLG_UNUSED     = 0x0020,
    LPFLG_CONST_INIT = 0x0040, // iterator is initialized with a constant (found in lpConstInit)
    LPFLG_SIMD_LIMIT = 0x0080, // iterator is compared with vector element count (found in lpConstLimit)

    LPFLG_VAR_LIMIT    = 0x0100, // iterator is compared with a local var (var # found in lpVarLimit)
    LPFLG_CONST_LIMIT  = 0x0200, // iterator is compared with a constant (found in lpConstLimit)
    LPFLG_ARRLEN_LIMIT = 0x0400, // iterator is compared with a.len or a[i].len (found in lpArrLenLimit)
    LPFLG_HAS_PREHEAD  = 0x0800, // lpHead is known to be a preHead for this loop

    LPFLG_REMOVED     = 0x1000, // has been removed from the loop table (unrolled or optimized away)
    LPFLG_DONT_UNROLL = 0x2000, // do not unroll this loop
    LPFLG_ASGVARS_YES = 0x4000, // "lpAsgVars" has been computed
    LPFLG_ASGVARS_INC = 0x8000, // "lpAsgVars" is incomplete -- vars beyond those representable in an AllVarSet
                                // type are assigned to.
};

inline constexpr LoopFlags operator~(LoopFlags a)
{
    return (LoopFlags)(~(unsigned short)a);
}

inline constexpr LoopFlags operator|(LoopFlags a, LoopFlags b)
{
    return (LoopFlags)((unsigned short)a | (unsigned short)b);
}

inline constexpr LoopFlags operator&(LoopFlags a, LoopFlags b)
{
    return (LoopFlags)((unsigned short)a & (unsigned short)b);
}

inline LoopFlags& operator|=(LoopFlags& a, LoopFlags b)
{
    return a = (LoopFlags)((unsigned short)a | (unsigned short)b);
}

inline LoopFlags& operator&=(LoopFlags& a, LoopFlags b)
{
    return a = (LoopFlags)((unsigned short)a & (unsigned short)b);
}

//  The following holds information about instr offsets in terms of generated code.

enum class IPmappingDscKind
{
    Prolog,    // The mapping represents the start of a prolog.
    Epilog,    // The mapping represents the start of an epilog.
    NoMapping, // This does not map to any IL offset.
    Normal,    // The mapping maps to an IL offset.
};

struct IPmappingDsc
{
    emitLocation     ipmdNativeLoc; // the emitter location of the native code corresponding to the IL offset
    IPmappingDscKind ipmdKind;      // The kind of mapping
    ILLocation       ipmdLoc;       // The location for normal mappings
    bool             ipmdIsLabel;   // Can this code be a branch label?
};

struct RichIPMapping
{
    emitLocation nativeLoc;
    DebugInfo    debugInfo;
};

/*
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XX                                                                           XX
XX   The big guy. The sections are currently organized as :                  XX
XX                                                                           XX
XX    o  GenTree and BasicBlock                                              XX
XX    o  LclVarsInfo                                                         XX
XX    o  Importer                                                            XX
XX    o  FlowGraph                                                           XX
XX    o  Optimizer                                                           XX
XX    o  RegAlloc                                                            XX
XX    o  EEInterface                                                         XX
XX    o  TempsInfo                                                           XX
XX    o  RegSet                                                              XX
XX    o  GCInfo                                                              XX
XX    o  Instruction                                                         XX
XX    o  ScopeInfo                                                           XX
XX    o  PrologScopeInfo                                                     XX
XX    o  CodeGenerator                                                       XX
XX    o  UnwindInfo                                                          XX
XX    o  Compiler                                                            XX
XX    o  typeInfo                                                            XX
XX                                                                           XX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
*/

struct HWIntrinsicInfo;

class Compiler
{
    friend class emitter;
    friend class UnwindInfo;
    friend class UnwindFragmentInfo;
    friend class UnwindEpilogInfo;
    friend class JitTimer;
    friend class LinearScan;
    friend class Rationalizer;
    friend class Phase;
    friend class Lowering;
    friend class CSE_DataFlow;
    friend class CSE_Heuristic;
    friend class CodeGenInterface;
    friend class CodeGen;
    friend class LclVarDsc;
    friend class TempDsc;
    friend class LIR;
    friend class ObjectAllocator;
    friend class LocalAddressVisitor;
    friend struct GenTree;
    friend class MorphInitBlockHelper;
    friend class MorphCopyBlockHelper;
    friend class CallArgs;
    friend class IndirectCallTransformer;

#ifdef FEATURE_HW_INTRINSICS
    friend struct HWIntrinsicInfo;
    friend struct SimdAsHWIntrinsicInfo;
#endif // FEATURE_HW_INTRINSICS

#ifndef TARGET_64BIT
    friend class DecomposeLongs;
#endif // !TARGET_64BIT

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX  Misc structs definitions                                                 XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */

public:
    hashBvGlobalData hbvGlobalData; // Used by the hashBv bitvector package.

#ifdef DEBUG
    bool verbose;
    bool verboseTrees;
    bool shouldUseVerboseTrees();
    bool asciiTrees; // If true, dump trees using only ASCII characters
    bool shouldDumpASCIITrees();
    bool verboseSsa; // If true, produce especially verbose dump output in SSA construction.
    bool shouldUseVerboseSsa();
    bool treesBeforeAfterMorph; // If true, print trees before/after morphing (paired by an intra-compilation id:
    int  morphNum;              // This counts the trees that have been morphed, allowing us to label each uniquely.
    bool doExtraSuperPmiQueries;
    void makeExtraStructQueries(CORINFO_CLASS_HANDLE structHandle, int level); // Make queries recursively 'level' deep.

    const char* VarNameToStr(VarName name)
    {
        return name;
    }

    DWORD expensiveDebugCheckLevel;
#endif

    GenTree* impAssignMultiRegTypeToVar(GenTree*             op,
                                        CORINFO_CLASS_HANDLE hClass DEBUGARG(CorInfoCallConvExtension callConv));

#ifdef TARGET_X86
    bool isTrivialPointerSizedStruct(CORINFO_CLASS_HANDLE clsHnd) const;
#endif // TARGET_X86

    //-------------------------------------------------------------------------
    // Functions to handle homogeneous floating-point aggregates (HFAs) in ARM/ARM64.
    // HFAs are one to four element structs where each element is the same
    // type, either all float or all double. We handle HVAs (one to four elements of
    // vector types) uniformly with HFAs. HFAs are treated specially
    // in the ARM/ARM64 Procedure Call Standards, specifically, they are passed in
    // floating-point registers instead of the general purpose registers.
    //

    bool IsHfa(CORINFO_CLASS_HANDLE hClass);
    var_types GetHfaType(CORINFO_CLASS_HANDLE hClass);
    unsigned GetHfaCount(CORINFO_CLASS_HANDLE hClass);

    bool IsMultiRegReturnedType(CORINFO_CLASS_HANDLE hClass, CorInfoCallConvExtension callConv);

    //-------------------------------------------------------------------------
    // The following is used for validating format of EH table
    //

    struct EHNodeDsc;
    typedef struct EHNodeDsc* pEHNodeDsc;

    EHNodeDsc* ehnTree; // root of the tree comprising the EHnodes.
    EHNodeDsc* ehnNext; // root of the tree comprising the EHnodes.

    struct EHNodeDsc
    {
        enum EHBlockType
        {
            TryNode,
            FilterNode,
            HandlerNode,
            FinallyNode,
            FaultNode
        };

        EHBlockType ehnBlockType;   // kind of EH block
        IL_OFFSET   ehnStartOffset; // IL offset of start of the EH block
        IL_OFFSET ehnEndOffset; // IL offset past end of the EH block. (TODO: looks like verInsertEhNode() sets this to
                                // the last IL offset, not "one past the last one", i.e., the range Start to End is
                                // inclusive).
        pEHNodeDsc ehnNext;     // next (non-nested) block in sequential order
        pEHNodeDsc ehnChild;    // leftmost nested block
        union {
            pEHNodeDsc ehnTryNode;     // for filters and handlers, the corresponding try node
            pEHNodeDsc ehnHandlerNode; // for a try node, the corresponding handler node
        };
        pEHNodeDsc ehnFilterNode; // if this is a try node and has a filter, otherwise 0
        pEHNodeDsc ehnEquivalent; // if blockType=tryNode, start offset and end offset is same,

        void ehnSetTryNodeType()
        {
            ehnBlockType = TryNode;
        }
        void ehnSetFilterNodeType()
        {
            ehnBlockType = FilterNode;
        }
        void ehnSetHandlerNodeType()
        {
            ehnBlockType = HandlerNode;
        }
        void ehnSetFinallyNodeType()
        {
            ehnBlockType = FinallyNode;
        }
        void ehnSetFaultNodeType()
        {
            ehnBlockType = FaultNode;
        }

        bool ehnIsTryBlock()
        {
            return ehnBlockType == TryNode;
        }
        bool ehnIsFilterBlock()
        {
            return ehnBlockType == FilterNode;
        }
        bool ehnIsHandlerBlock()
        {
            return ehnBlockType == HandlerNode;
        }
        bool ehnIsFinallyBlock()
        {
            return ehnBlockType == FinallyNode;
        }
        bool ehnIsFaultBlock()
        {
            return ehnBlockType == FaultNode;
        }

        // returns true if there is any overlap between the two nodes
        static bool ehnIsOverlap(pEHNodeDsc node1, pEHNodeDsc node2)
        {
            if (node1->ehnStartOffset < node2->ehnStartOffset)
            {
                return (node1->ehnEndOffset >= node2->ehnStartOffset);
            }
            else
            {
                return (node1->ehnStartOffset <= node2->ehnEndOffset);
            }
        }

        // fails with BADCODE if inner is not completely nested inside outer
        static bool ehnIsNested(pEHNodeDsc inner, pEHNodeDsc outer)
        {
            return ((inner->ehnStartOffset >= outer->ehnStartOffset) && (inner->ehnEndOffset <= outer->ehnEndOffset));
        }
    };

//-------------------------------------------------------------------------
// Exception handling functions
//

#if !defined(FEATURE_EH_FUNCLETS)

    bool ehNeedsShadowSPslots()
    {
        return (info.compXcptnsCount || opts.compDbgEnC);
    }

    // 0 for methods with no EH
    // 1 for methods with non-nested EH, or where only the try blocks are nested
    // 2 for a method with a catch within a catch
    // etc.
    unsigned ehMaxHndNestingCount;

#endif // !FEATURE_EH_FUNCLETS

    static bool jitIsBetween(unsigned value, unsigned start, unsigned end);
    static bool jitIsBetweenInclusive(unsigned value, unsigned start, unsigned end);

    bool bbInCatchHandlerILRange(BasicBlock* blk);
    bool bbInFilterILRange(BasicBlock* blk);
    bool bbInTryRegions(unsigned regionIndex, BasicBlock* blk);
    bool bbInExnFlowRegions(unsigned regionIndex, BasicBlock* blk);
    bool bbInHandlerRegions(unsigned regionIndex, BasicBlock* blk);
    bool bbInCatchHandlerRegions(BasicBlock* tryBlk, BasicBlock* hndBlk);
    unsigned short bbFindInnermostCommonTryRegion(BasicBlock* bbOne, BasicBlock* bbTwo);

    unsigned short bbFindInnermostTryRegionContainingHandlerRegion(unsigned handlerIndex);
    unsigned short bbFindInnermostHandlerRegionContainingTryRegion(unsigned tryIndex);

    // Returns true if "block" is the start of a try region.
    bool bbIsTryBeg(BasicBlock* block);

    // Returns true if "block" is the start of a handler or filter region.
    bool bbIsHandlerBeg(BasicBlock* block);

    // Returns true iff "block" is where control flows if an exception is raised in the
    // try region, and sets "*regionIndex" to the index of the try for the handler.
    // Differs from "IsHandlerBeg" in the case of filters, where this is true for the first
    // block of the filter, but not for the filter's handler.
    bool bbIsExFlowBlock(BasicBlock* block, unsigned* regionIndex);

    bool ehHasCallableHandlers();

    // Return the EH descriptor for the given region index.
    EHblkDsc* ehGetDsc(unsigned regionIndex);

    // Return the EH index given a region descriptor.
    unsigned ehGetIndex(EHblkDsc* ehDsc);

    // Return the EH descriptor index of the enclosing try, for the given region index.
    unsigned ehGetEnclosingTryIndex(unsigned regionIndex);

    // Return the EH descriptor index of the enclosing handler, for the given region index.
    unsigned ehGetEnclosingHndIndex(unsigned regionIndex);

    // Return the EH descriptor for the most nested 'try' region this BasicBlock is a member of (or nullptr if this
    // block is not in a 'try' region).
    EHblkDsc* ehGetBlockTryDsc(BasicBlock* block);

    // Return the EH descriptor for the most nested filter or handler region this BasicBlock is a member of (or nullptr
    // if this block is not in a filter or handler region).
    EHblkDsc* ehGetBlockHndDsc(BasicBlock* block);

    // Return the EH descriptor for the most nested region that may handle exceptions raised in this BasicBlock (or
    // nullptr if this block's exceptions propagate to caller).
    EHblkDsc* ehGetBlockExnFlowDsc(BasicBlock* block);

    EHblkDsc* ehIsBlockTryLast(BasicBlock* block);
    EHblkDsc* ehIsBlockHndLast(BasicBlock* block);
    bool ehIsBlockEHLast(BasicBlock* block);

    bool ehBlockHasExnFlowDsc(BasicBlock* block);

    // Return the region index of the most nested EH region this block is in.
    unsigned ehGetMostNestedRegionIndex(BasicBlock* block, bool* inTryRegion);

    // Find the true enclosing try index, ignoring 'mutual protect' try. Uses IL ranges to check.
    unsigned ehTrueEnclosingTryIndexIL(unsigned regionIndex);

    // Return the index of the most nested enclosing region for a particular EH region. Returns NO_ENCLOSING_INDEX
    // if there is no enclosing region. If the returned index is not NO_ENCLOSING_INDEX, then '*inTryRegion'
    // is set to 'true' if the enclosing region is a 'try', or 'false' if the enclosing region is a handler.
    // (It can never be a filter.)
    unsigned ehGetEnclosingRegionIndex(unsigned regionIndex, bool* inTryRegion);

    // A block has been deleted. Update the EH table appropriately.
    void ehUpdateForDeletedBlock(BasicBlock* block);

    // Determine whether a block can be deleted while preserving the EH normalization rules.
    bool ehCanDeleteEmptyBlock(BasicBlock* block);

    // Update the 'last' pointers in the EH table to reflect new or deleted blocks in an EH region.
    void ehUpdateLastBlocks(BasicBlock* oldLast, BasicBlock* newLast);

    // For a finally handler, find the region index that the BBJ_CALLFINALLY lives in that calls the handler,
    // or NO_ENCLOSING_INDEX if the BBJ_CALLFINALLY lives in the main function body. Normally, the index
    // is the same index as the handler (and the BBJ_CALLFINALLY lives in the 'try' region), but for AMD64 the
    // BBJ_CALLFINALLY lives in the enclosing try or handler region, whichever is more nested, or the main function
    // body. If the returned index is not NO_ENCLOSING_INDEX, then '*inTryRegion' is set to 'true' if the
    // BBJ_CALLFINALLY lives in the returned index's 'try' region, or 'false' if lives in the handler region. (It never
    // lives in a filter.)
    unsigned ehGetCallFinallyRegionIndex(unsigned finallyIndex, bool* inTryRegion);

    // Find the range of basic blocks in which all BBJ_CALLFINALLY will be found that target the 'finallyIndex' region's
    // handler. Set begBlk to the first block, and endBlk to the block after the last block of the range
    // (nullptr if the last block is the last block in the program).
    // Precondition: 'finallyIndex' is the EH region of a try/finally clause.
    void ehGetCallFinallyBlockRange(unsigned finallyIndex, BasicBlock** begBlk, BasicBlock** endBlk);

#ifdef DEBUG
    // Given a BBJ_CALLFINALLY block and the EH region index of the finally it is calling, return
    // 'true' if the BBJ_CALLFINALLY is in the correct EH region.
    bool ehCallFinallyInCorrectRegion(BasicBlock* blockCallFinally, unsigned finallyIndex);
#endif // DEBUG

#if defined(FEATURE_EH_FUNCLETS)
    // Do we need a PSPSym in the main function? For codegen purposes, we only need one
    // if there is a filter that protects a region with a nested EH clause (such as a
    // try/catch nested in the 'try' body of a try/filter/filter-handler). See
    // genFuncletProlog() for more details. However, the VM seems to use it for more
    // purposes, maybe including debugging. Until we are sure otherwise, always create
    // a PSPSym for functions with any EH.
    bool ehNeedsPSPSym() const
    {
#ifdef TARGET_X86
        return false;
#else  // TARGET_X86
        return compHndBBtabCount > 0;
#endif // TARGET_X86
    }

    bool     ehAnyFunclets();  // Are there any funclets in this function?
    unsigned ehFuncletCount(); // Return the count of funclets in the function

    unsigned bbThrowIndex(BasicBlock* blk); // Get the index to use as the cache key for sharing throw blocks

#else  // !FEATURE_EH_FUNCLETS

    bool ehAnyFunclets()
    {
        return false;
    }
    unsigned ehFuncletCount()
    {
        return 0;
    }

    unsigned bbThrowIndex(BasicBlock* blk)
    {
        return blk->bbTryIndex;
    } // Get the index to use as the cache key for sharing throw blocks
#endif // !FEATURE_EH_FUNCLETS

    // Returns a flowList representing the "EH predecessors" of "blk".  These are the normal predecessors of
    // "blk", plus one special case: if "blk" is the first block of a handler, considers the predecessor(s) of the first
    // first block of the corresponding try region to be "EH predecessors".  (If there is a single such predecessor,
    // for example, we want to consider that the immediate dominator of the catch clause start block, so it's
    // convenient to also consider it a predecessor.)
    flowList* BlockPredsWithEH(BasicBlock* blk);

    // This table is useful for memoization of the method above.
    typedef JitHashTable<BasicBlock*, JitPtrKeyFuncs<BasicBlock>, flowList*> BlockToFlowListMap;
    BlockToFlowListMap* m_blockToEHPreds;
    BlockToFlowListMap* GetBlockToEHPreds()
    {
        if (m_blockToEHPreds == nullptr)
        {
            m_blockToEHPreds = new (getAllocator()) BlockToFlowListMap(getAllocator());
        }
        return m_blockToEHPreds;
    }

    void* ehEmitCookie(BasicBlock* block);
    UNATIVE_OFFSET ehCodeOffset(BasicBlock* block);

    EHblkDsc* ehInitHndRange(BasicBlock* src, IL_OFFSET* hndBeg, IL_OFFSET* hndEnd, bool* inFilter);

    EHblkDsc* ehInitTryRange(BasicBlock* src, IL_OFFSET* tryBeg, IL_OFFSET* tryEnd);

    EHblkDsc* ehInitHndBlockRange(BasicBlock* blk, BasicBlock** hndBeg, BasicBlock** hndLast, bool* inFilter);

    EHblkDsc* ehInitTryBlockRange(BasicBlock* blk, BasicBlock** tryBeg, BasicBlock** tryLast);

    void fgSetTryBeg(EHblkDsc* handlerTab, BasicBlock* newTryBeg);

    void fgSetTryEnd(EHblkDsc* handlerTab, BasicBlock* newTryLast);

    void fgSetHndEnd(EHblkDsc* handlerTab, BasicBlock* newHndLast);

    void fgSkipRmvdBlocks(EHblkDsc* handlerTab);

    void fgAllocEHTable();

    void fgRemoveEHTableEntry(unsigned XTnum);

#if defined(FEATURE_EH_FUNCLETS)

    EHblkDsc* fgAddEHTableEntry(unsigned XTnum);

#endif // FEATURE_EH_FUNCLETS

#if !FEATURE_EH
    void fgRemoveEH();
#endif // !FEATURE_EH

    void fgSortEHTable();

    // Causes the EH table to obey some well-formedness conditions, by inserting
    // empty BB's when necessary:
    //   * No block is both the first block of a handler and the first block of a try.
    //   * No block is the first block of multiple 'try' regions.
    //   * No block is the last block of multiple EH regions.
    void fgNormalizeEH();
    bool fgNormalizeEHCase1();
    bool fgNormalizeEHCase2();
    bool fgNormalizeEHCase3();

    bool fgCreateFiltersForGenericExceptions();

    void fgCheckForLoopsInHandlers();

#ifdef DEBUG
    void dispIncomingEHClause(unsigned num, const CORINFO_EH_CLAUSE& clause);
    void dispOutgoingEHClause(unsigned num, const CORINFO_EH_CLAUSE& clause);
    void fgVerifyHandlerTab();
    void fgDispHandlerTab();
#endif // DEBUG

    bool fgNeedToSortEHTable;

    void verInitEHTree(unsigned numEHClauses);
    void verInsertEhNode(CORINFO_EH_CLAUSE* clause, EHblkDsc* handlerTab);
    void verInsertEhNodeInTree(EHNodeDsc** ppRoot, EHNodeDsc* node);
    void verInsertEhNodeParent(EHNodeDsc** ppRoot, EHNodeDsc* node);
    void verCheckNestingLevel(EHNodeDsc* initRoot);

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX                        GenTree and BasicBlock                             XX
    XX                                                                           XX
    XX  Functions to allocate and display the GenTrees and BasicBlocks           XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */

    // Functions to create nodes
    Statement* gtNewStmt(GenTree* expr = nullptr);
    Statement* gtNewStmt(GenTree* expr, const DebugInfo& di);

    // For unary opers.
    GenTree* gtNewOperNode(genTreeOps oper, var_types type, GenTree* op1);

    // For binary opers.
    GenTree* gtNewOperNode(genTreeOps oper, var_types type, GenTree* op1, GenTree* op2);

    GenTreeColon* gtNewColonNode(var_types type, GenTree* elseNode, GenTree* thenNode);
    GenTreeQmark* gtNewQmarkNode(var_types type, GenTree* cond, GenTreeColon* colon);

    GenTree* gtNewLargeOperNode(genTreeOps oper,
                                var_types  type = TYP_I_IMPL,
                                GenTree*   op1  = nullptr,
                                GenTree*   op2  = nullptr);

    GenTreeIntCon* gtNewIconNode(ssize_t value, var_types type = TYP_INT);
    GenTreeIntCon* gtNewIconNode(unsigned fieldOffset, FieldSeq* fieldSeq);
    GenTreeIntCon* gtNewNull();
    GenTreeIntCon* gtNewTrue();
    GenTreeIntCon* gtNewFalse();

    GenTree* gtNewPhysRegNode(regNumber reg, var_types type);

    GenTree* gtNewJmpTableNode();

    GenTree* gtNewIndOfIconHandleNode(var_types indType, size_t value, GenTreeFlags iconFlags, bool isInvariant);

    GenTreeIntCon* gtNewIconHandleNode(size_t value, GenTreeFlags flags, FieldSeq* fields = nullptr);

    GenTreeFlags gtTokenToIconFlags(unsigned token);

    GenTree* gtNewIconEmbHndNode(void* value, void* pValue, GenTreeFlags flags, void* compileTimeHandle);

    GenTree* gtNewIconEmbScpHndNode(CORINFO_MODULE_HANDLE scpHnd);
    GenTree* gtNewIconEmbClsHndNode(CORINFO_CLASS_HANDLE clsHnd);
    GenTree* gtNewIconEmbMethHndNode(CORINFO_METHOD_HANDLE methHnd);
    GenTree* gtNewIconEmbFldHndNode(CORINFO_FIELD_HANDLE fldHnd);

    GenTree* gtNewStringLiteralNode(InfoAccessType iat, void* pValue);
    GenTreeIntCon* gtNewStringLiteralLength(GenTreeStrCon* node);

    GenTree* gtNewLconNode(__int64 value);

    GenTree* gtNewDconNode(double value, var_types type = TYP_DOUBLE);

    GenTree* gtNewSconNode(int CPX, CORINFO_MODULE_HANDLE scpHandle);

    GenTreeVecCon* gtNewVconNode(var_types type);

    GenTree* gtNewAllBitsSetConNode(var_types type);

    GenTree* gtNewZeroConNode(var_types type);

    GenTree* gtNewOneConNode(var_types type, var_types simdBaseType = TYP_UNDEF);

    GenTreeLclVar* gtNewStoreLclVar(unsigned dstLclNum, GenTree* src);

    GenTree* gtNewBlkOpNode(GenTree* dst, GenTree* srcOrFillVal, bool isVolatile, bool isCopyBlock);

    GenTree* gtNewPutArgReg(var_types type, GenTree* arg, regNumber argReg);

    GenTree* gtNewBitCastNode(var_types type, GenTree* arg);

protected:
    void gtBlockOpInit(GenTree* result, GenTree* dst, GenTree* srcOrFillVal, bool isVolatile);

public:
    GenTreeObj* gtNewObjNode(ClassLayout* layout, GenTree* addr);
    GenTreeObj* gtNewObjNode(CORINFO_CLASS_HANDLE structHnd, GenTree* addr);
    void gtSetObjGcInfo(GenTreeObj* objNode);
    GenTree* gtNewStructVal(ClassLayout* layout, GenTree* addr);
    GenTree* gtNewBlockVal(GenTree* addr, unsigned size);

    GenTreeCall* gtNewCallNode(gtCallTypes           callType,
                               CORINFO_METHOD_HANDLE handle,
                               var_types             type,
                               const DebugInfo&      di = DebugInfo());

    GenTreeCall* gtNewIndCallNode(GenTree* addr, var_types type, const DebugInfo& di = DebugInfo());

    GenTreeCall* gtNewHelperCallNode(
        unsigned helper, var_types type, GenTree* arg1 = nullptr, GenTree* arg2 = nullptr, GenTree* arg3 = nullptr);

    GenTreeCall* gtNewRuntimeLookupHelperCallNode(CORINFO_RUNTIME_LOOKUP* pRuntimeLookup,
                                                  GenTree*                ctxTree,
                                                  void*                   compileTimeHandle);

    GenTreeLclVar* gtNewLclvNode(unsigned lnum, var_types type DEBUGARG(IL_OFFSET offs = BAD_IL_OFFSET));
    GenTreeLclVar* gtNewLclLNode(unsigned lnum, var_types type DEBUGARG(IL_OFFSET offs = BAD_IL_OFFSET));

    GenTreeLclVar* gtNewLclVarAddrNode(unsigned lclNum, var_types type = TYP_I_IMPL);
    GenTreeLclFld* gtNewLclFldAddrNode(unsigned lclNum, unsigned lclOffs, var_types type = TYP_I_IMPL);

    GenTreeConditional* gtNewConditionalNode(
        genTreeOps oper, GenTree* cond, GenTree* op1, GenTree* op2, var_types type);

#ifdef FEATURE_SIMD
    GenTreeSIMD* gtNewSIMDNode(
        var_types type, GenTree* op1, SIMDIntrinsicID simdIntrinsicID, CorInfoType simdBaseJitType, unsigned simdSize);
    GenTreeSIMD* gtNewSIMDNode(var_types       type,
                               GenTree*        op1,
                               GenTree*        op2,
                               SIMDIntrinsicID simdIntrinsicID,
                               CorInfoType     simdBaseJitType,
                               unsigned        simdSize);
    void SetOpLclRelatedToSIMDIntrinsic(GenTree* op);
#endif

#ifdef FEATURE_HW_INTRINSICS
    GenTreeHWIntrinsic* gtNewSimdHWIntrinsicNode(var_types      type,
                                                 NamedIntrinsic hwIntrinsicID,
                                                 CorInfoType    simdBaseJitType,
                                                 unsigned       simdSize,
                                                 bool           isSimdAsHWIntrinsic = false);
    GenTreeHWIntrinsic* gtNewSimdHWIntrinsicNode(var_types      type,
                                                 GenTree*       op1,
                                                 NamedIntrinsic hwIntrinsicID,
                                                 CorInfoType    simdBaseJitType,
                                                 unsigned       simdSize,
                                                 bool           isSimdAsHWIntrinsic = false);
    GenTreeHWIntrinsic* gtNewSimdHWIntrinsicNode(var_types      type,
                                                 GenTree*       op1,
                                                 GenTree*       op2,
                                                 NamedIntrinsic hwIntrinsicID,
                                                 CorInfoType    simdBaseJitType,
                                                 unsigned       simdSize,
                                                 bool           isSimdAsHWIntrinsic = false);
    GenTreeHWIntrinsic* gtNewSimdHWIntrinsicNode(var_types      type,
                                                 GenTree*       op1,
                                                 GenTree*       op2,
                                                 GenTree*       op3,
                                                 NamedIntrinsic hwIntrinsicID,
                                                 CorInfoType    simdBaseJitType,
                                                 unsigned       simdSize,
                                                 bool           isSimdAsHWIntrinsic = false);
    GenTreeHWIntrinsic* gtNewSimdHWIntrinsicNode(var_types      type,
                                                 GenTree*       op1,
                                                 GenTree*       op2,
                                                 GenTree*       op3,
                                                 GenTree*       op4,
                                                 NamedIntrinsic hwIntrinsicID,
                                                 CorInfoType    simdBaseJitType,
                                                 unsigned       simdSize,
                                                 bool           isSimdAsHWIntrinsic = false);
    GenTreeHWIntrinsic* gtNewSimdHWIntrinsicNode(var_types      type,
                                                 GenTree**      operands,
                                                 size_t         operandCount,
                                                 NamedIntrinsic hwIntrinsicID,
                                                 CorInfoType    simdBaseJitType,
                                                 unsigned       simdSize,
                                                 bool           isSimdAsHWIntrinsic = false);
    GenTreeHWIntrinsic* gtNewSimdHWIntrinsicNode(var_types              type,
                                                 IntrinsicNodeBuilder&& nodeBuilder,
                                                 NamedIntrinsic         hwIntrinsicID,
                                                 CorInfoType            simdBaseJitType,
                                                 unsigned               simdSize,
                                                 bool                   isSimdAsHWIntrinsic = false);

    GenTreeHWIntrinsic* gtNewSimdAsHWIntrinsicNode(var_types      type,
                                                   NamedIntrinsic hwIntrinsicID,
                                                   CorInfoType    simdBaseJitType,
                                                   unsigned       simdSize)
    {
        bool isSimdAsHWIntrinsic = true;
        return gtNewSimdHWIntrinsicNode(type, hwIntrinsicID, simdBaseJitType, simdSize, isSimdAsHWIntrinsic);
    }

    GenTreeHWIntrinsic* gtNewSimdAsHWIntrinsicNode(
        var_types type, GenTree* op1, NamedIntrinsic hwIntrinsicID, CorInfoType simdBaseJitType, unsigned simdSize)
    {
        bool isSimdAsHWIntrinsic = true;
        return gtNewSimdHWIntrinsicNode(type, op1, hwIntrinsicID, simdBaseJitType, simdSize, isSimdAsHWIntrinsic);
    }

    GenTreeHWIntrinsic* gtNewSimdAsHWIntrinsicNode(var_types      type,
                                                   GenTree*       op1,
                                                   GenTree*       op2,
                                                   NamedIntrinsic hwIntrinsicID,
                                                   CorInfoType    simdBaseJitType,
                                                   unsigned       simdSize)
    {
        bool isSimdAsHWIntrinsic = true;
        return gtNewSimdHWIntrinsicNode(type, op1, op2, hwIntrinsicID, simdBaseJitType, simdSize, isSimdAsHWIntrinsic);
    }

    GenTreeHWIntrinsic* gtNewSimdAsHWIntrinsicNode(var_types      type,
                                                   GenTree*       op1,
                                                   GenTree*       op2,
                                                   GenTree*       op3,
                                                   NamedIntrinsic hwIntrinsicID,
                                                   CorInfoType    simdBaseJitType,
                                                   unsigned       simdSize)
    {
        bool isSimdAsHWIntrinsic = true;
        return gtNewSimdHWIntrinsicNode(type, op1, op2, op3, hwIntrinsicID, simdBaseJitType, simdSize,
                                        isSimdAsHWIntrinsic);
    }

    GenTree* gtNewSimdAbsNode(
        var_types type, GenTree* op1, CorInfoType simdBaseJitType, unsigned simdSize, bool isSimdAsHWIntrinsic);

    GenTree* gtNewSimdBinOpNode(genTreeOps  op,
                                var_types   type,
                                GenTree*    op1,
                                GenTree*    op2,
                                CorInfoType simdBaseJitType,
                                unsigned    simdSize,
                                bool        isSimdAsHWIntrinsic);

    GenTree* gtNewSimdCeilNode(
        var_types type, GenTree* op1, CorInfoType simdBaseJitType, unsigned simdSize, bool isSimdAsHWIntrinsic);

    GenTree* gtNewSimdCmpOpNode(genTreeOps  op,
                                var_types   type,
                                GenTree*    op1,
                                GenTree*    op2,
                                CorInfoType simdBaseJitType,
                                unsigned    simdSize,
                                bool        isSimdAsHWIntrinsic);

    GenTree* gtNewSimdCmpOpAllNode(genTreeOps  op,
                                   var_types   type,
                                   GenTree*    op1,
                                   GenTree*    op2,
                                   CorInfoType simdBaseJitType,
                                   unsigned    simdSize,
                                   bool        isSimdAsHWIntrinsic);

    GenTree* gtNewSimdCmpOpAnyNode(genTreeOps  op,
                                   var_types   type,
                                   GenTree*    op1,
                                   GenTree*    op2,
                                   CorInfoType simdBaseJitType,
                                   unsigned    simdSize,
                                   bool        isSimdAsHWIntrinsic);

    GenTree* gtNewSimdCndSelNode(var_types   type,
                                 GenTree*    op1,
                                 GenTree*    op2,
                                 GenTree*    op3,
                                 CorInfoType simdBaseJitType,
                                 unsigned    simdSize,
                                 bool        isSimdAsHWIntrinsic);

    GenTree* gtNewSimdCreateBroadcastNode(
        var_types type, GenTree* op1, CorInfoType simdBaseJitType, unsigned simdSize, bool isSimdAsHWIntrinsic);

    GenTree* gtNewSimdDotProdNode(var_types   type,
                                  GenTree*    op1,
                                  GenTree*    op2,
                                  CorInfoType simdBaseJitType,
                                  unsigned    simdSize,
                                  bool        isSimdAsHWIntrinsic);

    GenTree* gtNewSimdFloorNode(
        var_types type, GenTree* op1, CorInfoType simdBaseJitType, unsigned simdSize, bool isSimdAsHWIntrinsic);

    GenTree* gtNewSimdGetElementNode(var_types   type,
                                     GenTree*    op1,
                                     GenTree*    op2,
                                     CorInfoType simdBaseJitType,
                                     unsigned    simdSize,
                                     bool        isSimdAsHWIntrinsic);

    GenTree* gtNewSimdMaxNode(var_types   type,
                              GenTree*    op1,
                              GenTree*    op2,
                              CorInfoType simdBaseJitType,
                              unsigned    simdSize,
                              bool        isSimdAsHWIntrinsic);

    GenTree* gtNewSimdMinNode(var_types   type,
                              GenTree*    op1,
                              GenTree*    op2,
                              CorInfoType simdBaseJitType,
                              unsigned    simdSize,
                              bool        isSimdAsHWIntrinsic);

    GenTree* gtNewSimdNarrowNode(var_types   type,
                                 GenTree*    op1,
                                 GenTree*    op2,
                                 CorInfoType simdBaseJitType,
                                 unsigned    simdSize,
                                 bool        isSimdAsHWIntrinsic);

    GenTree* gtNewSimdShuffleNode(var_types   type,
                                  GenTree*    op1,
                                  GenTree*    op2,
                                  CorInfoType simdBaseJitType,
                                  unsigned    simdSize,
                                  bool        isSimdAsHWIntrinsic);

    GenTree* gtNewSimdSqrtNode(
        var_types type, GenTree* op1, CorInfoType simdBaseJitType, unsigned simdSize, bool isSimdAsHWIntrinsic);

    GenTree* gtNewSimdSumNode(
        var_types type, GenTree* op1, CorInfoType simdBaseJitType, unsigned simdSize, bool isSimdAsHWIntrinsic);

    GenTree* gtNewSimdUnOpNode(genTreeOps  op,
                               var_types   type,
                               GenTree*    op1,
                               CorInfoType simdBaseJitType,
                               unsigned    simdSize,
                               bool        isSimdAsHWIntrinsic);

    GenTree* gtNewSimdWidenLowerNode(
        var_types type, GenTree* op1, CorInfoType simdBaseJitType, unsigned simdSize, bool isSimdAsHWIntrinsic);

    GenTree* gtNewSimdWidenUpperNode(
        var_types type, GenTree* op1, CorInfoType simdBaseJitType, unsigned simdSize, bool isSimdAsHWIntrinsic);

    GenTree* gtNewSimdWithElementNode(var_types   type,
                                      GenTree*    op1,
                                      GenTree*    op2,
                                      GenTree*    op3,
                                      CorInfoType simdBaseJitType,
                                      unsigned    simdSize,
                                      bool        isSimdAsHWIntrinsic);

    GenTreeHWIntrinsic* gtNewScalarHWIntrinsicNode(var_types type, NamedIntrinsic hwIntrinsicID);
    GenTreeHWIntrinsic* gtNewScalarHWIntrinsicNode(var_types type, GenTree* op1, NamedIntrinsic hwIntrinsicID);
    GenTreeHWIntrinsic* gtNewScalarHWIntrinsicNode(var_types      type,
                                                   GenTree*       op1,
                                                   GenTree*       op2,
                                                   NamedIntrinsic hwIntrinsicID);
    GenTreeHWIntrinsic* gtNewScalarHWIntrinsicNode(
        var_types type, GenTree* op1, GenTree* op2, GenTree* op3, NamedIntrinsic hwIntrinsicID);
    CORINFO_CLASS_HANDLE gtGetStructHandleForHWSIMD(var_types simdType, CorInfoType simdBaseJitType);
    CorInfoType getBaseJitTypeFromArgIfNeeded(NamedIntrinsic       intrinsic,
                                              CORINFO_CLASS_HANDLE clsHnd,
                                              CORINFO_SIG_INFO*    sig,
                                              CorInfoType          simdBaseJitType);
#endif // FEATURE_HW_INTRINSICS

    GenTree* gtNewMustThrowException(unsigned helper, var_types type, CORINFO_CLASS_HANDLE clsHnd);

    GenTreeLclFld* gtNewLclFldNode(unsigned lnum, var_types type, unsigned offset);
    GenTreeRetExpr* gtNewInlineCandidateReturnExpr(GenTreeCall* inlineCandidate, var_types type);

    GenTreeField* gtNewFieldRef(var_types type, CORINFO_FIELD_HANDLE fldHnd, GenTree* obj = nullptr, DWORD offset = 0);

    GenTreeField* gtNewFieldAddrNode(var_types            type,
                                     CORINFO_FIELD_HANDLE fldHnd,
                                     GenTree*             obj    = nullptr,
                                     DWORD                offset = 0);

    GenTreeIndexAddr* gtNewIndexAddr(GenTree*             arrayOp,
                                     GenTree*             indexOp,
                                     var_types            elemType,
                                     CORINFO_CLASS_HANDLE elemClassHandle,
                                     unsigned             firstElemOffset,
                                     unsigned             lengthOffset);

    GenTreeIndexAddr* gtNewArrayIndexAddr(GenTree*             arrayOp,
                                          GenTree*             indexOp,
                                          var_types            elemType,
                                          CORINFO_CLASS_HANDLE elemClassHandle);

    GenTreeIndir* gtNewIndexIndir(GenTreeIndexAddr* indexAddr);

    void gtAnnotateNewArrLen(GenTree* arrLen, BasicBlock* block);

    GenTreeArrLen* gtNewArrLen(var_types typ, GenTree* arrayOp, int lenOffset, BasicBlock* block);

    GenTreeMDArr* gtNewMDArrLen(GenTree* arrayOp, unsigned dim, unsigned rank, BasicBlock* block);

    GenTreeMDArr* gtNewMDArrLowerBound(GenTree* arrayOp, unsigned dim, unsigned rank, BasicBlock* block);

    GenTreeIndir* gtNewIndir(var_types typ, GenTree* addr, GenTreeFlags indirFlags = GTF_EMPTY);

    GenTree* gtNewNullCheck(GenTree* addr, BasicBlock* basicBlock);

    var_types gtTypeForNullCheck(GenTree* tree);
    void gtChangeOperToNullCheck(GenTree* tree, BasicBlock* block);

    GenTreeOp* gtNewAssignNode(GenTree* dst, GenTree* src);

    GenTree* gtNewTempAssign(unsigned         tmp,
                             GenTree*         val,
                             Statement**      pAfterStmt = nullptr,
                             const DebugInfo& di         = DebugInfo(),
                             BasicBlock*      block      = nullptr);

    GenTree* gtNewRefCOMfield(GenTree*                objPtr,
                              CORINFO_RESOLVED_TOKEN* pResolvedToken,
                              CORINFO_ACCESS_FLAGS    access,
                              CORINFO_FIELD_INFO*     pFieldInfo,
                              var_types               lclTyp,
                              CORINFO_CLASS_HANDLE    structType,
                              GenTree*                assg);

    GenTree* gtNewNothingNode();

    GenTree* gtUnusedValNode(GenTree* expr);

    GenTree* gtNewKeepAliveNode(GenTree* op);

    GenTreeCast* gtNewCastNode(var_types typ, GenTree* op1, bool fromUnsigned, var_types castType);

    GenTreeCast* gtNewCastNodeL(var_types typ, GenTree* op1, bool fromUnsigned, var_types castType);

    GenTreeAllocObj* gtNewAllocObjNode(
        unsigned int helper, bool helperHasSideEffects, CORINFO_CLASS_HANDLE clsHnd, var_types type, GenTree* op1);

    GenTreeAllocObj* gtNewAllocObjNode(CORINFO_RESOLVED_TOKEN* pResolvedToken, bool useParent);

    GenTree* gtNewRuntimeLookup(CORINFO_GENERIC_HANDLE hnd, CorInfoGenericHandleType hndTyp, GenTree* lookupTree);

    GenTreeIndir* gtNewMethodTableLookup(GenTree* obj);

    //------------------------------------------------------------------------
    // Other GenTree functions

    GenTree* gtClone(GenTree* tree, bool complexOK = false);

    // If `tree` is a lclVar with lclNum `varNum`, return an IntCns with value `varVal`; otherwise,
    // create a copy of `tree`, adding specified flags, replacing uses of lclVar `deepVarNum` with
    // IntCnses with value `deepVarVal`.
    GenTree* gtCloneExpr(
        GenTree* tree, GenTreeFlags addFlags, unsigned varNum, int varVal, unsigned deepVarNum, int deepVarVal);

    // Create a copy of `tree`, optionally adding specified flags, and optionally mapping uses of local
    // `varNum` to int constants with value `varVal`.
    GenTree* gtCloneExpr(GenTree*     tree,
                         GenTreeFlags addFlags = GTF_EMPTY,
                         unsigned     varNum   = BAD_VAR_NUM,
                         int          varVal   = 0)
    {
        return gtCloneExpr(tree, addFlags, varNum, varVal, varNum, varVal);
    }

    Statement* gtCloneStmt(Statement* stmt)
    {
        GenTree* exprClone = gtCloneExpr(stmt->GetRootNode());
        return gtNewStmt(exprClone, stmt->GetDebugInfo());
    }

    // Internal helper for cloning a call
    GenTreeCall* gtCloneExprCallHelper(GenTreeCall* call,
                                       GenTreeFlags addFlags   = GTF_EMPTY,
                                       unsigned     deepVarNum = BAD_VAR_NUM,
                                       int          deepVarVal = 0);

    // Create copy of an inline or guarded devirtualization candidate tree.
    GenTreeCall* gtCloneCandidateCall(GenTreeCall* call);

    void gtUpdateSideEffects(Statement* stmt, GenTree* tree);

    void gtUpdateTreeAncestorsSideEffects(GenTree* tree);

    void gtUpdateStmtSideEffects(Statement* stmt);

    void gtUpdateNodeSideEffects(GenTree* tree);

    void gtUpdateNodeOperSideEffects(GenTree* tree);

    // Returns "true" iff the complexity (not formally defined, but first interpretation
    // is #of nodes in subtree) of "tree" is greater than "limit".
    // (This is somewhat redundant with the "GetCostEx()/GetCostSz()" fields, but can be used
    // before they have been set.)
    bool gtComplexityExceeds(GenTree** tree, unsigned limit);

    GenTree* gtReverseCond(GenTree* tree);

    static bool gtHasRef(GenTree* tree, unsigned lclNum);

    bool gtHasLocalsWithAddrOp(GenTree* tree);

    unsigned gtSetCallArgsOrder(CallArgs* args, bool lateArgs, int* callCostEx, int* callCostSz);
    unsigned gtSetMultiOpOrder(GenTreeMultiOp* multiOp);

    void gtWalkOp(GenTree** op1, GenTree** op2, GenTree* base, bool constOnly);

#ifdef DEBUG
    unsigned gtHashValue(GenTree* tree);

    GenTree* gtWalkOpEffectiveVal(GenTree* op);
#endif

    void gtPrepareCost(GenTree* tree);
    bool gtIsLikelyRegVar(GenTree* tree);

    // Returns true iff the secondNode can be swapped with firstNode.
    bool gtCanSwapOrder(GenTree* firstNode, GenTree* secondNode);

    // Given an address expression, compute its costs and addressing mode opportunities,
    // and mark addressing mode candidates as GTF_DONT_CSE.
    // TODO-Throughput - Consider actually instantiating these early, to avoid
    // having to re-run the algorithm that looks for them (might also improve CQ).
    bool gtMarkAddrMode(GenTree* addr, int* costEx, int* costSz, var_types type);

    unsigned gtSetEvalOrder(GenTree* tree);

    void gtSetStmtInfo(Statement* stmt);

    // Returns "true" iff "node" has any of the side effects in "flags".
    bool gtNodeHasSideEffects(GenTree* node, GenTreeFlags flags);

    // Returns "true" iff "tree" or its (transitive) children have any of the side effects in "flags".
    bool gtTreeHasSideEffects(GenTree* tree, GenTreeFlags flags);

    // Appends 'expr' in front of 'list'
    //    'list' will typically start off as 'nullptr'
    //    when 'list' is non-null a GT_COMMA node is used to insert 'expr'
    GenTree* gtBuildCommaList(GenTree* list, GenTree* expr);

    void gtExtractSideEffList(GenTree*     expr,
                              GenTree**    pList,
                              GenTreeFlags GenTreeFlags = GTF_SIDE_EFFECT,
                              bool         ignoreRoot   = false);

    // Static fields of struct types (and sometimes the types that those are reduced to) are represented by having the
    // static field contain an object pointer to the boxed struct.  This simplifies the GC implementation...but
    // complicates the JIT somewhat.  This predicate returns "true" iff a node with type "fieldNodeType", representing
    // the given "fldHnd", is such an object pointer.
    bool gtIsStaticFieldPtrToBoxedStruct(var_types fieldNodeType, CORINFO_FIELD_HANDLE fldHnd);

    bool gtStoreDefinesField(
        LclVarDsc* fieldVarDsc, ssize_t offset, unsigned size, ssize_t* pFieldStoreOffset, unsigned* pFieldStoreSize);

    // Return true if call is a recursive call; return false otherwise.
    // Note when inlining, this looks for calls back to the root method.
    bool gtIsRecursiveCall(GenTreeCall* call)
    {
        return gtIsRecursiveCall(call->gtCallMethHnd);
    }

    bool gtIsRecursiveCall(CORINFO_METHOD_HANDLE callMethodHandle)
    {
        return (callMethodHandle == impInlineRoot()->info.compMethodHnd);
    }

    //-------------------------------------------------------------------------

    GenTree* gtFoldExpr(GenTree* tree);
    GenTree* gtFoldExprConst(GenTree* tree);
    GenTree* gtFoldIndirConst(GenTreeIndir* indir);
    GenTree* gtFoldExprSpecial(GenTree* tree);
    GenTree* gtFoldBoxNullable(GenTree* tree);
    GenTree* gtFoldExprCompare(GenTree* tree);
    GenTree* gtFoldExprConditional(GenTree* tree);
    GenTree* gtCreateHandleCompare(genTreeOps             oper,
                                   GenTree*               op1,
                                   GenTree*               op2,
                                   CorInfoInlineTypeCheck typeCheckInliningResult);
    GenTree* gtFoldExprCall(GenTreeCall* call);
    GenTree* gtFoldTypeCompare(GenTree* tree);
    GenTree* gtFoldTypeEqualityCall(bool isEq, GenTree* op1, GenTree* op2);

    // Options to control behavior of gtTryRemoveBoxUpstreamEffects
    enum BoxRemovalOptions
    {
        BR_REMOVE_AND_NARROW, // remove effects, minimize remaining work, return possibly narrowed source tree
        BR_REMOVE_AND_NARROW_WANT_TYPE_HANDLE, // remove effects and minimize remaining work, return type handle tree
        BR_REMOVE_BUT_NOT_NARROW,              // remove effects, return original source tree
        BR_DONT_REMOVE,                        // check if removal is possible, return copy source tree
        BR_DONT_REMOVE_WANT_TYPE_HANDLE,       // check if removal is possible, return type handle tree
        BR_MAKE_LOCAL_COPY                     // revise box to copy to temp local and return local's address
    };

    GenTree* gtTryRemoveBoxUpstreamEffects(GenTree* tree, BoxRemovalOptions options = BR_REMOVE_AND_NARROW);
    GenTree* gtOptimizeEnumHasFlag(GenTree* thisOp, GenTree* flagOp);

    //-------------------------------------------------------------------------
    // Get the handle, if any.
    CORINFO_CLASS_HANDLE gtGetStructHandleIfPresent(GenTree* tree);
    // Get the handle, and assert if not found.
    CORINFO_CLASS_HANDLE gtGetStructHandle(GenTree* tree);
    // Get the handle for a ref type.
    CORINFO_CLASS_HANDLE gtGetClassHandle(GenTree* tree, bool* pIsExact, bool* pIsNonNull);
    // Get the class handle for an helper call
    CORINFO_CLASS_HANDLE gtGetHelperCallClassHandle(GenTreeCall* call, bool* pIsExact, bool* pIsNonNull);
    // Get the element handle for an array of ref type.
    CORINFO_CLASS_HANDLE gtGetArrayElementClassHandle(GenTree* array);
    // Get a class handle from a helper call argument
    CORINFO_CLASS_HANDLE gtGetHelperArgClassHandle(GenTree* array);
    // Get the class handle for a field
    CORINFO_CLASS_HANDLE gtGetFieldClassHandle(CORINFO_FIELD_HANDLE fieldHnd, bool* pIsExact, bool* pIsNonNull);
    // Check if this tree is a typeof()
    bool gtIsTypeof(GenTree* tree, CORINFO_CLASS_HANDLE* handle = nullptr);

    GenTree* gtCallGetDefinedRetBufLclAddr(GenTreeCall* call);

//-------------------------------------------------------------------------
// Functions to display the trees

#ifdef DEBUG
    void gtDispNode(GenTree* tree, IndentStack* indentStack, _In_z_ const char* msg, bool isLIR);

    void gtDispConst(GenTree* tree);
    void gtDispLeaf(GenTree* tree, IndentStack* indentStack);
    void gtDispNodeName(GenTree* tree);
#if FEATURE_MULTIREG_RET
    unsigned gtDispMultiRegCount(GenTree* tree);
#endif
    void gtDispRegVal(GenTree* tree);
    void gtDispVN(GenTree* tree);
    void gtDispCommonEndLine(GenTree* tree);

    enum IndentInfo
    {
        IINone,
        IIArc,
        IIArcTop,
        IIArcBottom,
        IIEmbedded,
        IIError,
        IndentInfoCount
    };
    void gtDispChild(GenTree*             child,
                     IndentStack*         indentStack,
                     IndentInfo           arcType,
                     _In_opt_ const char* msg     = nullptr,
                     bool                 topOnly = false);
    void gtDispTree(GenTree*             tree,
                    IndentStack*         indentStack = nullptr,
                    _In_opt_ const char* msg         = nullptr,
                    bool                 topOnly     = false,
                    bool                 isLIR       = false);
    void gtGetLclVarNameInfo(unsigned lclNum, const char** ilKindOut, const char** ilNameOut, unsigned* ilNumOut);
    int gtGetLclVarName(unsigned lclNum, char* buf, unsigned buf_remaining);
    char* gtGetLclVarName(unsigned lclNum);
    void gtDispLclVar(unsigned lclNum, bool padForBiggestDisp = true);
    void gtDispLclVarStructType(unsigned lclNum);
    void gtDispSsaName(unsigned lclNum, unsigned ssaNum, bool isDef);
    void gtDispClassLayout(ClassLayout* layout, var_types type);
    void gtDispILLocation(const ILLocation& loc);
    void gtDispStmt(Statement* stmt, const char* msg = nullptr);
    void gtDispBlockStmts(BasicBlock* block);
    void gtPrintArgPrefix(GenTreeCall* call, CallArg* arg, char** bufp, unsigned* bufLength);
    const char* gtGetWellKnownArgNameForArgMsg(WellKnownArg arg);
    void gtGetArgMsg(GenTreeCall* call, CallArg* arg, char* bufp, unsigned bufLength);
    void gtGetLateArgMsg(GenTreeCall* call, CallArg* arg, char* bufp, unsigned bufLength);
    void gtDispArgList(GenTreeCall* call, GenTree* lastCallOperand, IndentStack* indentStack);
    void gtDispFieldSeq(FieldSeq* fieldSeq, ssize_t offset);

    void gtDispRange(LIR::ReadOnlyRange const& range);

    void gtDispTreeRange(LIR::Range& containingRange, GenTree* tree);

    void gtDispLIRNode(GenTree* node, const char* prefixMsg = nullptr);
#endif

    // For tree walks

    enum fgWalkResult
    {
        WALK_CONTINUE,
        WALK_SKIP_SUBTREES,
        WALK_ABORT
    };
    struct fgWalkData;
    typedef fgWalkResult(fgWalkPreFn)(GenTree** pTree, fgWalkData* data);
    typedef fgWalkResult(fgWalkPostFn)(GenTree** pTree, fgWalkData* data);

    static fgWalkPreFn gtMarkColonCond;
    static fgWalkPreFn gtClearColonCond;

    struct FindLinkData
    {
        GenTree*  nodeToFind;
        GenTree** result;
        GenTree*  parent;
    };

    FindLinkData gtFindLink(Statement* stmt, GenTree* node);
    bool gtHasCatchArg(GenTree* tree);

    typedef ArrayStack<GenTree*> GenTreeStack;

    static bool gtHasCallOnStack(GenTreeStack* parentStack);

//=========================================================================
// BasicBlock functions
#ifdef DEBUG
    // This is a debug flag we will use to assert when creating block during codegen
    // as this interferes with procedure splitting. If you know what you're doing, set
    // it to true before creating the block. (DEBUG only)
    bool fgSafeBasicBlockCreation;
#endif

    BasicBlock* bbNewBasicBlock(BBjumpKinds jumpKind);

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX                           LclVarsInfo                                     XX
    XX                                                                           XX
    XX   The variables to be used by the code generator.                         XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */

    //
    // For both PROMOTION_TYPE_NONE and PROMOTION_TYPE_DEPENDENT the struct will
    // be placed in the stack frame and it's fields must be laid out sequentially.
    //
    // For PROMOTION_TYPE_INDEPENDENT each of the struct's fields is replaced by
    //  a local variable that can be enregistered or placed in the stack frame.
    //  The fields do not need to be laid out sequentially
    //
    enum lvaPromotionType
    {
        PROMOTION_TYPE_NONE,        // The struct local is not promoted
        PROMOTION_TYPE_INDEPENDENT, // The struct local is promoted,
                                    //   and its field locals are independent of its parent struct local.
        PROMOTION_TYPE_DEPENDENT    // The struct local is promoted,
                                    //   but its field locals depend on its parent struct local.
    };

    /*****************************************************************************/

    enum FrameLayoutState
    {
        NO_FRAME_LAYOUT,
        INITIAL_FRAME_LAYOUT,
        PRE_REGALLOC_FRAME_LAYOUT,
        REGALLOC_FRAME_LAYOUT,
        TENTATIVE_FRAME_LAYOUT,
        FINAL_FRAME_LAYOUT
    };

public:
    RefCountState lvaRefCountState; // Current local ref count state

    bool lvaLocalVarRefCounted() const
    {
        return lvaRefCountState == RCS_NORMAL;
    }

    bool     lvaTrackedFixed; // true: We cannot add new 'tracked' variable
    unsigned lvaCount;        // total number of locals, which includes function arguments,
                              // special arguments, IL local variables, and JIT temporary variables

    LclVarDsc* lvaTable;    // variable descriptor table
    unsigned   lvaTableCnt; // lvaTable size (>= lvaCount)

    unsigned lvaTrackedCount;             // actual # of locals being tracked
    unsigned lvaTrackedCountInSizeTUnits; // min # of size_t's sufficient to hold a bit for all the locals being tracked

#ifdef DEBUG
    VARSET_TP lvaTrackedVars; // set of tracked variables
#endif
#ifndef TARGET_64BIT
    VARSET_TP lvaLongVars; // set of long (64-bit) variables
#endif
    VARSET_TP lvaFloatVars; // set of floating-point (32-bit and 64-bit) variables

    unsigned lvaCurEpoch; // VarSets are relative to a specific set of tracked var indices.
                          // It that changes, this changes.  VarSets from different epochs
                          // cannot be meaningfully combined.

    unsigned GetCurLVEpoch()
    {
        return lvaCurEpoch;
    }

    // reverse map of tracked number to var number
    unsigned  lvaTrackedToVarNumSize;
    unsigned* lvaTrackedToVarNum;

#if DOUBLE_ALIGN
#ifdef DEBUG
    // # of procs compiled a with double-aligned stack
    static unsigned s_lvaDoubleAlignedProcsCount;
#endif
#endif

    // Getters and setters for address-exposed and do-not-enregister local var properties.
    bool lvaVarAddrExposed(unsigned varNum) const;
    void lvaSetVarAddrExposed(unsigned varNum DEBUGARG(AddressExposedReason reason));
    void lvaSetHiddenBufferStructArg(unsigned varNum);
    void lvaSetVarLiveInOutOfHandler(unsigned varNum);
    bool lvaVarDoNotEnregister(unsigned varNum);

    void lvSetMinOptsDoNotEnreg();

    bool lvaEnregEHVars;
    bool lvaEnregMultiRegVars;

    void lvaSetVarDoNotEnregister(unsigned varNum DEBUGARG(DoNotEnregisterReason reason));

    unsigned lvaVarargsHandleArg;
#ifdef TARGET_X86
    unsigned lvaVarargsBaseOfStkArgs; // Pointer (computed based on incoming varargs handle) to the start of the stack
                                      // arguments
#endif                                // TARGET_X86

    unsigned lvaInlinedPInvokeFrameVar; // variable representing the InlinedCallFrame
    unsigned lvaReversePInvokeFrameVar; // variable representing the reverse PInvoke frame
#if FEATURE_FIXED_OUT_ARGS
    unsigned lvaPInvokeFrameRegSaveVar; // variable representing the RegSave for PInvoke inlining.
#endif
    unsigned lvaMonAcquired; // boolean variable introduced into in synchronized methods
                             // that tracks whether the lock has been taken

    unsigned lvaArg0Var; // The lclNum of arg0. Normally this will be info.compThisArg.
                         // However, if there is a "ldarga 0" or "starg 0" in the IL,
                         // we will redirect all "ldarg(a) 0" and "starg 0" to this temp.

    unsigned lvaInlineeReturnSpillTemp; // The temp to spill the non-VOID return expression
                                        // in case there are multiple BBJ_RETURN blocks in the inlinee
                                        // or if the inlinee has GC ref locals.

#if FEATURE_FIXED_OUT_ARGS
    unsigned            lvaOutgoingArgSpaceVar;  // dummy TYP_LCLBLK var for fixed outgoing argument space
    PhasedVar<unsigned> lvaOutgoingArgSpaceSize; // size of fixed outgoing argument space
#endif                                           // FEATURE_FIXED_OUT_ARGS

    static unsigned GetOutgoingArgByteSize(unsigned sizeWithoutPadding)
    {
        return roundUp(sizeWithoutPadding, TARGET_POINTER_SIZE);
    }

    // Variable representing the return address. The helper-based tailcall
    // mechanism passes the address of the return address to a runtime helper
    // where it is used to detect tail-call chains.
    unsigned lvaRetAddrVar;

#if defined(DEBUG) && defined(TARGET_XARCH)

    unsigned lvaReturnSpCheck; // Stores SP to confirm it is not corrupted on return.

#endif // defined(DEBUG) && defined(TARGET_XARCH)

#if defined(DEBUG) && defined(TARGET_X86)

    unsigned lvaCallSpCheck; // Stores SP to confirm it is not corrupted after every call.

#endif // defined(DEBUG) && defined(TARGET_X86)

    bool lvaGenericsContextInUse;

    bool lvaKeepAliveAndReportThis(); // Synchronized instance method of a reference type, or
                                      // CORINFO_GENERICS_CTXT_FROM_THIS?
    bool lvaReportParamTypeArg();     // Exceptions and CORINFO_GENERICS_CTXT_FROM_PARAMTYPEARG?

//-------------------------------------------------------------------------
// All these frame offsets are inter-related and must be kept in sync

#if !defined(FEATURE_EH_FUNCLETS)
    // This is used for the callable handlers
    unsigned lvaShadowSPslotsVar; // TYP_BLK variable for all the shadow SP slots
#endif                            // FEATURE_EH_FUNCLETS

    int lvaCachedGenericContextArgOffs;
    int lvaCachedGenericContextArgOffset(); // For CORINFO_CALLCONV_PARAMTYPE and if generic context is passed as
                                            // THIS pointer

#ifdef JIT32_GCENCODER

    unsigned lvaLocAllocSPvar; // variable which stores the value of ESP after the last alloca/localloc

#endif // JIT32_GCENCODER

    unsigned lvaNewObjArrayArgs; // variable with arguments for new MD array helper

    // TODO-Review: Prior to reg predict we reserve 24 bytes for Spill temps.
    //              after the reg predict we will use a computed maxTmpSize
    //              which is based upon the number of spill temps predicted by reg predict
    //              All this is necessary because if we under-estimate the size of the spill
    //              temps we could fail when encoding instructions that reference stack offsets for ARM.
    //
    // Pre codegen max spill temp size.
    static const unsigned MAX_SPILL_TEMP_SIZE = 24;

    //-------------------------------------------------------------------------

    unsigned lvaGetMaxSpillTempSize();
#ifdef TARGET_ARM
    bool lvaIsPreSpilled(unsigned lclNum, regMaskTP preSpillMask);
#endif // TARGET_ARM
    void lvaAssignFrameOffsets(FrameLayoutState curState);
    void lvaFixVirtualFrameOffsets();
    void lvaUpdateArgWithInitialReg(LclVarDsc* varDsc);
    void lvaUpdateArgsWithInitialReg();
    void lvaAssignVirtualFrameOffsetsToArgs();
#ifdef UNIX_AMD64_ABI
    int lvaAssignVirtualFrameOffsetToArg(unsigned lclNum, unsigned argSize, int argOffs, int* callerArgOffset);
#else  // !UNIX_AMD64_ABI
    int lvaAssignVirtualFrameOffsetToArg(unsigned lclNum, unsigned argSize, int argOffs);
#endif // !UNIX_AMD64_ABI
    void lvaAssignVirtualFrameOffsetsToLocals();
    int lvaAllocLocalAndSetVirtualOffset(unsigned lclNum, unsigned size, int stkOffs);
#ifdef TARGET_AMD64
    // Returns true if compCalleeRegsPushed (including RBP if used as frame pointer) is even.
    bool lvaIsCalleeSavedIntRegCountEven();
#endif
    void lvaAlignFrame();
    void lvaAssignFrameOffsetsToPromotedStructs();
    int lvaAllocateTemps(int stkOffs, bool mustDoubleAlign);

#ifdef DEBUG
    void lvaDumpRegLocation(unsigned lclNum);
    void lvaDumpFrameLocation(unsigned lclNum);
    void lvaDumpEntry(unsigned lclNum, FrameLayoutState curState, size_t refCntWtdWidth = 6);
    void lvaTableDump(FrameLayoutState curState = NO_FRAME_LAYOUT); // NO_FRAME_LAYOUT means use the current frame
                                                                    // layout state defined by lvaDoneFrameLayout
#endif

// Limit frames size to 1GB. The maximum is 2GB in theory - make it intentionally smaller
// to avoid bugs from borderline cases.
#define MAX_FrameSize 0x3FFFFFFF
    void lvaIncrementFrameSize(unsigned size);

    unsigned lvaFrameSize(FrameLayoutState curState);

    // Returns the caller-SP-relative offset for the SP/FP relative offset determined by FP based.
    int lvaToCallerSPRelativeOffset(int offs, bool isFpBased, bool forRootFrame = true) const;

    // Returns the caller-SP-relative offset for the local variable "varNum."
    int lvaGetCallerSPRelativeOffset(unsigned varNum);

    // Returns the SP-relative offset for the local variable "varNum". Illegal to ask this for functions with localloc.
    int lvaGetSPRelativeOffset(unsigned varNum);

    int lvaToInitialSPRelativeOffset(unsigned offset, bool isFpBased);
    int lvaGetInitialSPRelativeOffset(unsigned varNum);

    // True if this is an OSR compilation and this local is potentially
    // located on the original method stack frame.
    bool lvaIsOSRLocal(unsigned varNum);

    //------------------------ For splitting types ----------------------------

    void lvaInitTypeRef();

    void lvaInitArgs(InitVarDscInfo* varDscInfo);
    void lvaInitThisPtr(InitVarDscInfo* varDscInfo);
    void lvaInitRetBuffArg(InitVarDscInfo* varDscInfo, bool useFixedRetBufReg);
    void lvaInitUserArgs(InitVarDscInfo* varDscInfo, unsigned skipArgs, unsigned takeArgs);
    void lvaInitGenericsCtxt(InitVarDscInfo* varDscInfo);
    void lvaInitVarArgsHandle(InitVarDscInfo* varDscInfo);

    void lvaInitVarDsc(LclVarDsc*              varDsc,
                       unsigned                varNum,
                       CorInfoType             corInfoType,
                       CORINFO_CLASS_HANDLE    typeHnd,
                       CORINFO_ARG_LIST_HANDLE varList,
                       CORINFO_SIG_INFO*       varSig);

    var_types lvaGetActualType(unsigned lclNum);
    var_types lvaGetRealType(unsigned lclNum);

    //-------------------------------------------------------------------------

    void lvaInit();

    LclVarDsc* lvaGetDesc(unsigned lclNum)
    {
        assert(lclNum < lvaCount);
        return &lvaTable[lclNum];
    }

    LclVarDsc* lvaGetDesc(unsigned lclNum) const
    {
        assert(lclNum < lvaCount);
        return &lvaTable[lclNum];
    }

    LclVarDsc* lvaGetDesc(const GenTreeLclVarCommon* lclVar)
    {
        return lvaGetDesc(lclVar->GetLclNum());
    }

    unsigned lvaTrackedIndexToLclNum(unsigned trackedIndex)
    {
        assert(trackedIndex < lvaTrackedCount);
        unsigned lclNum = lvaTrackedToVarNum[trackedIndex];
        assert(lclNum < lvaCount);
        return lclNum;
    }

    LclVarDsc* lvaGetDescByTrackedIndex(unsigned trackedIndex)
    {
        return lvaGetDesc(lvaTrackedIndexToLclNum(trackedIndex));
    }

    unsigned lvaGetLclNum(const LclVarDsc* varDsc)
    {
        assert((lvaTable <= varDsc) && (varDsc < lvaTable + lvaCount)); // varDsc must point within the table
        assert(((char*)varDsc - (char*)lvaTable) % sizeof(LclVarDsc) ==
               0); // varDsc better not point in the middle of a variable
        unsigned varNum = (unsigned)(varDsc - lvaTable);
        assert(varDsc == &lvaTable[varNum]);
        return varNum;
    }

    unsigned lvaLclSize(unsigned varNum);
    unsigned lvaLclExactSize(unsigned varNum);

    bool lvaHaveManyLocals() const;

    unsigned lvaGrabTemp(bool shortLifetime DEBUGARG(const char* reason));
    unsigned lvaGrabTemps(unsigned cnt DEBUGARG(const char* reason));
    unsigned lvaGrabTempWithImplicitUse(bool shortLifetime DEBUGARG(const char* reason));

    void lvaSortByRefCount();

    PhaseStatus lvaMarkLocalVars(); // Local variable ref-counting
    void lvaComputeRefCounts(bool isRecompute, bool setSlotNumbers);
    void lvaMarkLocalVars(BasicBlock* block, bool isRecompute);

    void lvaAllocOutgoingArgSpaceVar(); // Set up lvaOutgoingArgSpaceVar

#ifdef DEBUG
    struct lvaStressLclFldArgs
    {
        Compiler* m_pCompiler;
        bool      m_bFirstPass;
    };

    static fgWalkPreFn lvaStressLclFldCB;
    void               lvaStressLclFld();
    unsigned lvaStressLclFldPadding(unsigned lclNum);

    void lvaDispVarSet(VARSET_VALARG_TP set, VARSET_VALARG_TP allVars);
    void lvaDispVarSet(VARSET_VALARG_TP set);

#endif

#ifdef TARGET_ARM
    int lvaFrameAddress(int varNum, bool mustBeFPBased, regNumber* pBaseReg, int addrModeOffset, bool isFloatUsage);
#else
    int lvaFrameAddress(int varNum, bool* pFPbased);
#endif

    bool lvaIsParameter(unsigned varNum);
    bool lvaIsRegArgument(unsigned varNum);
    bool lvaIsOriginalThisArg(unsigned varNum); // Is this varNum the original this argument?
    bool lvaIsOriginalThisReadOnly();           // return true if there is no place in the code
                                                // that writes to arg0

#ifdef TARGET_X86
    bool lvaIsArgAccessedViaVarArgsCookie(unsigned lclNum)
    {
        if (!info.compIsVarArgs)
        {
            return false;
        }

        LclVarDsc* varDsc = lvaGetDesc(lclNum);
        return varDsc->lvIsParam && !varDsc->lvIsRegArg && (lclNum != lvaVarargsHandleArg);
    }
#endif // TARGET_X86

    bool lvaIsImplicitByRefLocal(unsigned lclNum) const;
    bool lvaIsLocalImplicitlyAccessedByRef(unsigned lclNum) const;

    // Returns true if this local var is a multireg struct
    bool lvaIsMultiregStruct(LclVarDsc* varDsc, bool isVararg);

    // If the local is a TYP_STRUCT, get/set a class handle describing it
    CORINFO_CLASS_HANDLE lvaGetStruct(unsigned varNum);
    void lvaSetStruct(unsigned varNum, CORINFO_CLASS_HANDLE typeHnd, bool unsafeValueClsCheck);
    void lvaSetStructUsedAsVarArg(unsigned varNum);

    // If the local is TYP_REF, set or update the associated class information.
    void lvaSetClass(unsigned varNum, CORINFO_CLASS_HANDLE clsHnd, bool isExact = false);
    void lvaSetClass(unsigned varNum, GenTree* tree, CORINFO_CLASS_HANDLE stackHandle = nullptr);
    void lvaUpdateClass(unsigned varNum, CORINFO_CLASS_HANDLE clsHnd, bool isExact = false);
    void lvaUpdateClass(unsigned varNum, GenTree* tree, CORINFO_CLASS_HANDLE stackHandle = nullptr);

#define MAX_NumOfFieldsInPromotableStruct 4 // Maximum number of fields in promotable struct

    // Info about struct type fields.
    struct lvaStructFieldInfo
    {
        CORINFO_FIELD_HANDLE fldHnd;
        unsigned char        fldOffset;
        unsigned char        fldOrdinal;
        var_types            fldType;
        unsigned             fldSize;
        CORINFO_CLASS_HANDLE fldTypeHnd;

        lvaStructFieldInfo()
            : fldHnd(nullptr), fldOffset(0), fldOrdinal(0), fldType(TYP_UNDEF), fldSize(0), fldTypeHnd(nullptr)
        {
        }
    };

    // Info about a struct type, instances of which may be candidates for promotion.
    struct lvaStructPromotionInfo
    {
        CORINFO_CLASS_HANDLE typeHnd;
        bool                 canPromote;
        bool                 containsHoles;
        bool                 customLayout;
        bool                 fieldsSorted;
        unsigned char        fieldCnt;
        lvaStructFieldInfo   fields[MAX_NumOfFieldsInPromotableStruct];

        lvaStructPromotionInfo(CORINFO_CLASS_HANDLE typeHnd = nullptr)
            : typeHnd(typeHnd)
            , canPromote(false)
            , containsHoles(false)
            , customLayout(false)
            , fieldsSorted(false)
            , fieldCnt(0)
        {
        }
    };

    struct lvaFieldOffsetCmp
    {
        bool operator()(const lvaStructFieldInfo& field1, const lvaStructFieldInfo& field2);
    };

    // This class is responsible for checking validity and profitability of struct promotion.
    // If it is both legal and profitable, then TryPromoteStructVar promotes the struct and initializes
    // necessary information for fgMorphStructField to use.
    class StructPromotionHelper
    {
    public:
        StructPromotionHelper(Compiler* compiler);

        bool CanPromoteStructType(CORINFO_CLASS_HANDLE typeHnd);
        bool TryPromoteStructVar(unsigned lclNum);
        void Clear()
        {
            structPromotionInfo.typeHnd = NO_CLASS_HANDLE;
        }

    private:
        bool CanPromoteStructVar(unsigned lclNum);
        bool ShouldPromoteStructVar(unsigned lclNum);
        void PromoteStructVar(unsigned lclNum);
        void SortStructFields();

        bool CanConstructAndPromoteField(lvaStructPromotionInfo* structPromotionInfo);

        lvaStructFieldInfo GetFieldInfo(CORINFO_FIELD_HANDLE fieldHnd, BYTE ordinal);
        bool TryPromoteStructField(lvaStructFieldInfo& outerFieldInfo);

    private:
        Compiler*              compiler;
        lvaStructPromotionInfo structPromotionInfo;
    };

    StructPromotionHelper* structPromotionHelper;

    unsigned lvaGetFieldLocal(const LclVarDsc* varDsc, unsigned int fldOffset);
    lvaPromotionType lvaGetPromotionType(const LclVarDsc* varDsc);
    lvaPromotionType lvaGetPromotionType(unsigned varNum);
    lvaPromotionType lvaGetParentPromotionType(const LclVarDsc* varDsc);
    lvaPromotionType lvaGetParentPromotionType(unsigned varNum);
    bool lvaIsFieldOfDependentlyPromotedStruct(const LclVarDsc* varDsc);
    bool lvaIsGCTracked(const LclVarDsc* varDsc);

#if defined(FEATURE_SIMD)
    bool lvaMapSimd12ToSimd16(const LclVarDsc* varDsc)
    {
        assert(varDsc->lvType == TYP_SIMD12);
        assert(varDsc->lvExactSize == 12);

#if defined(TARGET_64BIT)
        assert(compMacOsArm64Abi() || varDsc->lvSize() == 16);
#endif // defined(TARGET_64BIT)

        // We make local variable SIMD12 types 16 bytes instead of just 12.
        // lvSize() will return 16 bytes for SIMD12, even for fields.
        // However, we can't do that mapping if the var is a dependently promoted struct field.
        // Such a field must remain its exact size within its parent struct unless it is a single
        // field *and* it is the only field in a struct of 16 bytes.
        if (varDsc->lvSize() != 16)
        {
            return false;
        }
        if (lvaIsFieldOfDependentlyPromotedStruct(varDsc))
        {
            LclVarDsc* parentVarDsc = lvaGetDesc(varDsc->lvParentLcl);
            return (parentVarDsc->lvFieldCnt == 1) && (parentVarDsc->lvSize() == 16);
        }
        return true;
    }
#endif // defined(FEATURE_SIMD)

    unsigned lvaGSSecurityCookie; // LclVar number
    bool     lvaTempsHaveLargerOffsetThanVars();

    // Returns "true" iff local variable "lclNum" is in SSA form.
    bool lvaInSsa(unsigned lclNum) const
    {
        return lvaGetDesc(lclNum)->lvInSsa;
    }

    unsigned lvaStubArgumentVar; // variable representing the secret stub argument coming in EAX

#if defined(FEATURE_EH_FUNCLETS)
    unsigned lvaPSPSym; // variable representing the PSPSym
#endif

    InlineInfo*     impInlineInfo; // Only present for inlinees
    InlineStrategy* m_inlineStrategy;

    InlineContext* compInlineContext; // Always present

    // The Compiler* that is the root of the inlining tree of which "this" is a member.
    Compiler* impInlineRoot();

#if defined(DEBUG) || defined(INLINE_DATA)
    unsigned __int64 getInlineCycleCount()
    {
        return m_compCycles;
    }
#endif // defined(DEBUG) || defined(INLINE_DATA)

    bool fgNoStructPromotion;      // Set to TRUE to turn off struct promotion for this method.
    bool fgNoStructParamPromotion; // Set to TRUE to turn off struct promotion for parameters this method.

    //=========================================================================
    //                          PROTECTED
    //=========================================================================

protected:
    //---------------- Local variable ref-counting ----------------------------

    void lvaMarkLclRefs(GenTree* tree, BasicBlock* block, Statement* stmt, bool isRecompute);
    bool IsDominatedByExceptionalEntry(BasicBlock* block);
    void SetVolatileHint(LclVarDsc* varDsc);

    // Keeps the mapping from SSA #'s to VN's for the implicit memory variables.
    SsaDefArray<SsaMemDef> lvMemoryPerSsaData;

public:
    // Returns the address of the per-Ssa data for memory at the given ssaNum (which is required
    // not to be the SsaConfig::RESERVED_SSA_NUM, which indicates that the variable is
    // not an SSA variable).
    SsaMemDef* GetMemoryPerSsaData(unsigned ssaNum)
    {
        return lvMemoryPerSsaData.GetSsaDef(ssaNum);
    }

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX                           Importer                                        XX
    XX                                                                           XX
    XX   Imports the given method and converts it to semantic trees              XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */

private:
    // For prefixFlags
    enum
    {
        PREFIX_TAILCALL_EXPLICIT = 0x00000001, // call has "tail" IL prefix
        PREFIX_TAILCALL_IMPLICIT =
            0x00000010, // call is treated as having "tail" prefix even though there is no "tail" IL prefix
        PREFIX_TAILCALL_STRESS =
            0x00000100, // call doesn't "tail" IL prefix but is treated as explicit because of tail call stress
        PREFIX_TAILCALL    = (PREFIX_TAILCALL_EXPLICIT | PREFIX_TAILCALL_IMPLICIT | PREFIX_TAILCALL_STRESS),
        PREFIX_VOLATILE    = 0x00001000,
        PREFIX_UNALIGNED   = 0x00010000,
        PREFIX_CONSTRAINED = 0x00100000,
        PREFIX_READONLY    = 0x01000000
    };

    static void impValidateMemoryAccessOpcode(const BYTE* codeAddr, const BYTE* codeEndp, bool volatilePrefix);
    static OPCODE impGetNonPrefixOpcode(const BYTE* codeAddr, const BYTE* codeEndp);
    static bool impOpcodeIsCallOpcode(OPCODE opcode);

public:
    void impInit();
    void impImport();

    CORINFO_CLASS_HANDLE impGetRefAnyClass();
    CORINFO_CLASS_HANDLE impGetRuntimeArgumentHandle();
    CORINFO_CLASS_HANDLE impGetTypeHandleClass();
    CORINFO_CLASS_HANDLE impGetStringClass();
    CORINFO_CLASS_HANDLE impGetObjectClass();

    // Returns underlying type of handles returned by ldtoken instruction
    var_types GetRuntimeHandleUnderlyingType()
    {
        // RuntimeTypeHandle is backed by raw pointer on NativeAOT and by object reference on other runtimes
        return IsTargetAbi(CORINFO_NATIVEAOT_ABI) ? TYP_I_IMPL : TYP_REF;
    }

    void impDevirtualizeCall(GenTreeCall*            call,
                             CORINFO_RESOLVED_TOKEN* pResolvedToken,
                             CORINFO_METHOD_HANDLE*  method,
                             unsigned*               methodFlags,
                             CORINFO_CONTEXT_HANDLE* contextHandle,
                             CORINFO_CONTEXT_HANDLE* exactContextHandle,
                             bool                    isLateDevirtualization,
                             bool                    isExplicitTailCall,
                             IL_OFFSET               ilOffset = BAD_IL_OFFSET);

    bool impConsiderCallProbe(GenTreeCall* call, IL_OFFSET ilOffset);

    enum class GDVProbeType
    {
        None,
        ClassProfile,
        MethodProfile,
        MethodAndClassProfile,
    };

    GDVProbeType compClassifyGDVProbeType(GenTreeCall* call);

    //=========================================================================
    //                          PROTECTED
    //=========================================================================

protected:
    //-------------------- Stack manipulation ---------------------------------

    unsigned impStkSize; // Size of the full stack

#define SMALL_STACK_SIZE 16 // number of elements in impSmallStack

    struct SavedStack // used to save/restore stack contents.
    {
        unsigned    ssDepth; // number of values on stack
        StackEntry* ssTrees; // saved tree values
    };

    bool impIsPrimitive(CorInfoType type);
    bool impILConsumesAddr(const BYTE* codeAddr);

    void impResolveToken(const BYTE* addr, CORINFO_RESOLVED_TOKEN* pResolvedToken, CorInfoTokenKind kind);

    void impPushOnStack(GenTree* tree, typeInfo ti);
    void       impPushNullObjRefOnStack();
    StackEntry impPopStack();
    void impPopStack(unsigned n);
    StackEntry& impStackTop(unsigned n = 0);
    unsigned impStackHeight();

    void impSaveStackState(SavedStack* savePtr, bool copy);
    void impRestoreStackState(SavedStack* savePtr);

    GenTree* impImportLdvirtftn(GenTree* thisPtr, CORINFO_RESOLVED_TOKEN* pResolvedToken, CORINFO_CALL_INFO* pCallInfo);

    enum class BoxPatterns
    {
        None                  = 0,
        IsByRefLike           = 1,
        MakeInlineObservation = 2,
    };

    int impBoxPatternMatch(CORINFO_RESOLVED_TOKEN* pResolvedToken,
                           const BYTE*             codeAddr,
                           const BYTE*             codeEndp,
                           BoxPatterns             opts);
    void impImportAndPushBox(CORINFO_RESOLVED_TOKEN* pResolvedToken);

    void impImportNewObjArray(CORINFO_RESOLVED_TOKEN* pResolvedToken, CORINFO_CALL_INFO* pCallInfo);

    bool impCanPInvokeInline();
    bool impCanPInvokeInlineCallSite(BasicBlock* block);
    void impCheckForPInvokeCall(
        GenTreeCall* call, CORINFO_METHOD_HANDLE methHnd, CORINFO_SIG_INFO* sig, unsigned mflags, BasicBlock* block);
    GenTreeCall* impImportIndirectCall(CORINFO_SIG_INFO* sig, const DebugInfo& di = DebugInfo());
    void impPopArgsForUnmanagedCall(GenTreeCall* call, CORINFO_SIG_INFO* sig);

    void impInsertHelperCall(CORINFO_HELPER_DESC* helperCall);
    void impHandleAccessAllowed(CorInfoIsAccessAllowedResult result, CORINFO_HELPER_DESC* helperCall);
    void impHandleAccessAllowedInternal(CorInfoIsAccessAllowedResult result, CORINFO_HELPER_DESC* helperCall);

    var_types impImportCall(OPCODE                  opcode,
                            CORINFO_RESOLVED_TOKEN* pResolvedToken,
                            CORINFO_RESOLVED_TOKEN* pConstrainedResolvedToken, // Is this a "constrained." call on a
                                                                               // type parameter?
                            GenTree*           newobjThis,
                            int                prefixFlags,
                            CORINFO_CALL_INFO* callInfo,
                            IL_OFFSET          rawILOffset);

    CORINFO_CLASS_HANDLE impGetSpecialIntrinsicExactReturnType(GenTreeCall* call);

    GenTree* impFixupCallStructReturn(GenTreeCall* call, CORINFO_CLASS_HANDLE retClsHnd);

    GenTree* impFixupStructReturnType(GenTree* op);

#ifdef DEBUG
    var_types impImportJitTestLabelMark(int numArgs);
#endif // DEBUG

    GenTree* impInitClass(CORINFO_RESOLVED_TOKEN* pResolvedToken);

    GenTree* impImportStaticReadOnlyField(CORINFO_FIELD_HANDLE field, CORINFO_CLASS_HANDLE ownerCls);
    GenTree* impImportCnsTreeFromBuffer(uint8_t* buffer, var_types valueType);

    GenTree* impImportStaticFieldAccess(CORINFO_RESOLVED_TOKEN* pResolvedToken,
                                        CORINFO_ACCESS_FLAGS    access,
                                        CORINFO_FIELD_INFO*     pFieldInfo,
                                        var_types               lclTyp);

    static void impBashVarAddrsToI(GenTree* tree1, GenTree* tree2 = nullptr);

    GenTree* impImplicitIorI4Cast(GenTree* tree, var_types dstTyp);

    GenTree* impImplicitR4orR8Cast(GenTree* tree, var_types dstTyp);

    void impImportLeave(BasicBlock* block);
    void impResetLeaveBlock(BasicBlock* block, unsigned jmpAddr);
    GenTree* impTypeIsAssignable(GenTree* typeTo, GenTree* typeFrom);

    // Mirrors StringComparison.cs
    enum StringComparison
    {
        Ordinal           = 4,
        OrdinalIgnoreCase = 5
    };
    enum StringComparisonJoint
    {
        Eq,  // (d1 == cns1) && (s2 == cns2)
        Xor, // (d1 ^ cns1) | (s2 ^ cns2)
    };
    GenTree* impStringEqualsOrStartsWith(bool startsWith, CORINFO_SIG_INFO* sig, unsigned methodFlags);
    GenTree* impSpanEqualsOrStartsWith(bool startsWith, CORINFO_SIG_INFO* sig, unsigned methodFlags);
    GenTree* impExpandHalfConstEquals(GenTreeLclVar*   data,
                                      GenTree*         lengthFld,
                                      bool             checkForNull,
                                      bool             startsWith,
                                      WCHAR*           cnsData,
                                      int              len,
                                      int              dataOffset,
                                      StringComparison cmpMode);
    GenTree* impCreateCompareInd(GenTreeLclVar*        obj,
                                 var_types             type,
                                 ssize_t               offset,
                                 ssize_t               value,
                                 StringComparison      ignoreCase,
                                 StringComparisonJoint joint = Eq);
    GenTree* impExpandHalfConstEqualsSWAR(
        GenTreeLclVar* data, WCHAR* cns, int len, int dataOffset, StringComparison cmpMode);
    GenTree* impExpandHalfConstEqualsSIMD(
        GenTreeLclVar* data, WCHAR* cns, int len, int dataOffset, StringComparison cmpMode);
    GenTreeStrCon* impGetStrConFromSpan(GenTree* span);

    GenTree* impIntrinsic(GenTree*                newobjThis,
                          CORINFO_CLASS_HANDLE    clsHnd,
                          CORINFO_METHOD_HANDLE   method,
                          CORINFO_SIG_INFO*       sig,
                          unsigned                methodFlags,
                          int                     memberRef,
                          bool                    readonlyCall,
                          bool                    tailCall,
                          CORINFO_RESOLVED_TOKEN* pContstrainedResolvedToken,
                          CORINFO_THIS_TRANSFORM  constraintCallThisTransform,
                          NamedIntrinsic*         pIntrinsicName,
                          bool*                   isSpecialIntrinsic = nullptr);
    GenTree* impMathIntrinsic(CORINFO_METHOD_HANDLE method,
                              CORINFO_SIG_INFO*     sig,
                              var_types             callType,
                              NamedIntrinsic        intrinsicName,
                              bool                  tailCall);
    NamedIntrinsic lookupNamedIntrinsic(CORINFO_METHOD_HANDLE method);
    GenTree* impUnsupportedNamedIntrinsic(unsigned              helper,
                                          CORINFO_METHOD_HANDLE method,
                                          CORINFO_SIG_INFO*     sig,
                                          bool                  mustExpand);

    GenTree* impSRCSUnsafeIntrinsic(NamedIntrinsic        intrinsic,
                                    CORINFO_CLASS_HANDLE  clsHnd,
                                    CORINFO_METHOD_HANDLE method,
                                    CORINFO_SIG_INFO*     sig);

#ifdef FEATURE_HW_INTRINSICS
    GenTree* impHWIntrinsic(NamedIntrinsic        intrinsic,
                            CORINFO_CLASS_HANDLE  clsHnd,
                            CORINFO_METHOD_HANDLE method,
                            CORINFO_SIG_INFO*     sig,
                            bool                  mustExpand);
    GenTree* impSimdAsHWIntrinsic(NamedIntrinsic        intrinsic,
                                  CORINFO_CLASS_HANDLE  clsHnd,
                                  CORINFO_METHOD_HANDLE method,
                                  CORINFO_SIG_INFO*     sig,
                                  GenTree*              newobjThis);

protected:
    bool compSupportsHWIntrinsic(CORINFO_InstructionSet isa);

    GenTree* impSimdAsHWIntrinsicSpecial(NamedIntrinsic       intrinsic,
                                         CORINFO_CLASS_HANDLE clsHnd,
                                         CORINFO_SIG_INFO*    sig,
                                         var_types            retType,
                                         CorInfoType          simdBaseJitType,
                                         unsigned             simdSize,
                                         GenTree*             newobjThis);

    GenTree* impSpecialIntrinsic(NamedIntrinsic        intrinsic,
                                 CORINFO_CLASS_HANDLE  clsHnd,
                                 CORINFO_METHOD_HANDLE method,
                                 CORINFO_SIG_INFO*     sig,
                                 CorInfoType           simdBaseJitType,
                                 var_types             retType,
                                 unsigned              simdSize);

    GenTree* getArgForHWIntrinsic(var_types            argType,
                                  CORINFO_CLASS_HANDLE argClass,
                                  bool                 expectAddr = false,
                                  GenTree*             newobjThis = nullptr);
    GenTree* impNonConstFallback(NamedIntrinsic intrinsic, var_types simdType, CorInfoType simdBaseJitType);
    GenTree* addRangeCheckIfNeeded(
        NamedIntrinsic intrinsic, GenTree* immOp, bool mustExpand, int immLowerBound, int immUpperBound);
    GenTree* addRangeCheckForHWIntrinsic(GenTree* immOp, int immLowerBound, int immUpperBound);

#ifdef TARGET_XARCH
    GenTree* impBaseIntrinsic(NamedIntrinsic        intrinsic,
                              CORINFO_CLASS_HANDLE  clsHnd,
                              CORINFO_METHOD_HANDLE method,
                              CORINFO_SIG_INFO*     sig,
                              CorInfoType           simdBaseJitType,
                              var_types             retType,
                              unsigned              simdSize);
    GenTree* impSSEIntrinsic(NamedIntrinsic intrinsic, CORINFO_METHOD_HANDLE method, CORINFO_SIG_INFO* sig);
    GenTree* impSSE2Intrinsic(NamedIntrinsic intrinsic, CORINFO_METHOD_HANDLE method, CORINFO_SIG_INFO* sig);
    GenTree* impAvxOrAvx2Intrinsic(NamedIntrinsic intrinsic, CORINFO_METHOD_HANDLE method, CORINFO_SIG_INFO* sig);
    GenTree* impBMI1OrBMI2Intrinsic(NamedIntrinsic intrinsic, CORINFO_METHOD_HANDLE method, CORINFO_SIG_INFO* sig);

    GenTree* impSerializeIntrinsic(NamedIntrinsic intrinsic, CORINFO_METHOD_HANDLE method, CORINFO_SIG_INFO* sig);
#endif // TARGET_XARCH
#endif // FEATURE_HW_INTRINSICS
    GenTree* impArrayAccessIntrinsic(CORINFO_CLASS_HANDLE clsHnd,
                                     CORINFO_SIG_INFO*    sig,
                                     int                  memberRef,
                                     bool                 readonlyCall,
                                     NamedIntrinsic       intrinsicName);
    GenTree* impInitializeArrayIntrinsic(CORINFO_SIG_INFO* sig);
    GenTree* impCreateSpanIntrinsic(CORINFO_SIG_INFO* sig);

    GenTree* impKeepAliveIntrinsic(GenTree* objToKeepAlive);

    GenTree* impMethodPointer(CORINFO_RESOLVED_TOKEN* pResolvedToken, CORINFO_CALL_INFO* pCallInfo);

    GenTree* impTransformThis(GenTree*                thisPtr,
                              CORINFO_RESOLVED_TOKEN* pConstrainedResolvedToken,
                              CORINFO_THIS_TRANSFORM  transform);

    //----------------- Manipulating the trees and stmts ----------------------

    Statement* impStmtList; // Statements for the BB being imported.
    Statement* impLastStmt; // The last statement for the current BB.

public:
    static const unsigned CHECK_SPILL_ALL  = static_cast<unsigned>(-1);
    static const unsigned CHECK_SPILL_NONE = static_cast<unsigned>(-2);

    void impBeginTreeList();
    void impEndTreeList(BasicBlock* block, Statement* firstStmt, Statement* lastStmt);
    void impEndTreeList(BasicBlock* block);
    void impAppendStmtCheck(Statement* stmt, unsigned chkLevel);
    void impAppendStmt(Statement* stmt, unsigned chkLevel, bool checkConsumedDebugInfo = true);
    void impAppendStmt(Statement* stmt);
    void impInsertStmtBefore(Statement* stmt, Statement* stmtBefore);
    Statement* impAppendTree(GenTree* tree, unsigned chkLevel, const DebugInfo& di, bool checkConsumedDebugInfo = true);
    void impInsertTreeBefore(GenTree* tree, const DebugInfo& di, Statement* stmtBefore);
    void impAssignTempGen(unsigned         tmp,
                          GenTree*         val,
                          unsigned         curLevel   = CHECK_SPILL_NONE,
                          Statement**      pAfterStmt = nullptr,
                          const DebugInfo& di         = DebugInfo(),
                          BasicBlock*      block      = nullptr);
    void impAssignTempGen(unsigned             tmpNum,
                          GenTree*             val,
                          CORINFO_CLASS_HANDLE structHnd,
                          unsigned             curLevel,
                          Statement**          pAfterStmt = nullptr,
                          const DebugInfo&     di         = DebugInfo(),
                          BasicBlock*          block      = nullptr);

    Statement* impExtractLastStmt();
    GenTree* impCloneExpr(GenTree*             tree,
                          GenTree**            clone,
                          CORINFO_CLASS_HANDLE structHnd,
                          unsigned             curLevel,
                          Statement** pAfterStmt DEBUGARG(const char* reason));
    GenTree* impAssignStruct(GenTree*             dest,
                             GenTree*             src,
                             CORINFO_CLASS_HANDLE structHnd,
                             unsigned             curLevel,
                             Statement**          pAfterStmt = nullptr,
                             const DebugInfo&     di         = DebugInfo(),
                             BasicBlock*          block      = nullptr);
    GenTree* impAssignStructPtr(GenTree*             dest,
                                GenTree*             src,
                                CORINFO_CLASS_HANDLE structHnd,
                                unsigned             curLevel,
                                Statement**          pAfterStmt = nullptr,
                                const DebugInfo&     di         = DebugInfo(),
                                BasicBlock*          block      = nullptr);

    GenTree* impGetStructAddr(GenTree* structVal, CORINFO_CLASS_HANDLE structHnd, unsigned curLevel, bool willDeref);

    var_types impNormStructType(CORINFO_CLASS_HANDLE structHnd, CorInfoType* simdBaseJitType = nullptr);

    GenTree* impNormStructVal(GenTree* structVal, CORINFO_CLASS_HANDLE structHnd, unsigned curLevel);

    GenTree* impTokenToHandle(CORINFO_RESOLVED_TOKEN* pResolvedToken,
                              bool*                   pRuntimeLookup    = nullptr,
                              bool                    mustRestoreHandle = false,
                              bool                    importParent      = false);

    GenTree* impParentClassTokenToHandle(CORINFO_RESOLVED_TOKEN* pResolvedToken,
                                         bool*                   pRuntimeLookup    = nullptr,
                                         bool                    mustRestoreHandle = false)
    {
        return impTokenToHandle(pResolvedToken, pRuntimeLookup, mustRestoreHandle, true);
    }

    GenTree* impLookupToTree(CORINFO_RESOLVED_TOKEN* pResolvedToken,
                             CORINFO_LOOKUP*         pLookup,
                             GenTreeFlags            flags,
                             void*                   compileTimeHandle);

    GenTree* getRuntimeContextTree(CORINFO_RUNTIME_LOOKUP_KIND kind);

    GenTree* impRuntimeLookupToTree(CORINFO_RESOLVED_TOKEN* pResolvedToken,
                                    CORINFO_LOOKUP*         pLookup,
                                    void*                   compileTimeHandle);

    GenTree* impReadyToRunLookupToTree(CORINFO_CONST_LOOKUP* pLookup, GenTreeFlags flags, void* compileTimeHandle);

    GenTreeCall* impReadyToRunHelperToTree(CORINFO_RESOLVED_TOKEN* pResolvedToken,
                                           CorInfoHelpFunc         helper,
                                           var_types               type,
                                           CORINFO_LOOKUP_KIND*    pGenericLookupKind = nullptr,
                                           GenTree*                arg1               = nullptr);

    bool impIsCastHelperEligibleForClassProbe(GenTree* tree);
    bool impIsCastHelperMayHaveProfileData(CorInfoHelpFunc helper);

    GenTree* impCastClassOrIsInstToTree(
        GenTree* op1, GenTree* op2, CORINFO_RESOLVED_TOKEN* pResolvedToken, bool isCastClass, IL_OFFSET ilOffset);

    GenTree* impOptimizeCastClassOrIsInst(GenTree* op1, CORINFO_RESOLVED_TOKEN* pResolvedToken, bool isCastClass);

    bool VarTypeIsMultiByteAndCanEnreg(var_types                type,
                                       CORINFO_CLASS_HANDLE     typeClass,
                                       unsigned*                typeSize,
                                       bool                     forReturn,
                                       bool                     isVarArg,
                                       CorInfoCallConvExtension callConv);

    bool IsIntrinsicImplementedByUserCall(NamedIntrinsic intrinsicName);
    bool IsTargetIntrinsic(NamedIntrinsic intrinsicName);
    bool IsMathIntrinsic(NamedIntrinsic intrinsicName);
    bool IsMathIntrinsic(GenTree* tree);

private:
    //----------------- Importing the method ----------------------------------

    CORINFO_CONTEXT_HANDLE impTokenLookupContextHandle; // The context used for looking up tokens.

#ifdef DEBUG
    unsigned    impCurOpcOffs;
    const char* impCurOpcName;
    bool        impNestedStackSpill;

    // For displaying instrs with generated native code (-n:B)
    Statement* impLastILoffsStmt; // oldest stmt added for which we did not call SetLastILOffset().
    void       impNoteLastILoffs();
#endif

    // Debug info of current statement being imported. It gets set to contain
    // no IL location (!impCurStmtDI.GetLocation().IsValid) after it has been
    // set in the appended trees. Then it gets updated at IL instructions for
    // which we have to report mapping info.
    // It will always contain the current inline context.
    DebugInfo impCurStmtDI;

    DebugInfo impCreateDIWithCurrentStackInfo(IL_OFFSET offs, bool isCall);
    void impCurStmtOffsSet(IL_OFFSET offs);

    void impNoteBranchOffs();

    unsigned impInitBlockLineInfo();

    bool impIsThis(GenTree* obj);

    void impPopCallArgs(CORINFO_SIG_INFO* sig, GenTreeCall* call);

public:
    static bool impCheckImplicitArgumentCoercion(var_types sigType, var_types nodeType);

private:
    void impPopReverseCallArgs(CORINFO_SIG_INFO* sig, GenTreeCall* call, unsigned skipReverseCount);

    //---------------- Spilling the importer stack ----------------------------

    // The maximum number of bytes of IL processed without clean stack state.
    // It allows to limit the maximum tree size and depth.
    static const unsigned MAX_TREE_SIZE = 200;
    bool impCanSpillNow(OPCODE prevOpcode);

    struct PendingDsc
    {
        PendingDsc* pdNext;
        BasicBlock* pdBB;
        SavedStack  pdSavedStack;
    };

    PendingDsc* impPendingList; // list of BBs currently waiting to be imported.
    PendingDsc* impPendingFree; // Freed up dscs that can be reused

    // We keep a byte-per-block map (dynamically extended) in the top-level Compiler object of a compilation.
    JitExpandArray<BYTE> impPendingBlockMembers;

    // Return the byte for "b" (allocating/extending impPendingBlockMembers if necessary.)
    // Operates on the map in the top-level ancestor.
    BYTE impGetPendingBlockMember(BasicBlock* blk)
    {
        return impInlineRoot()->impPendingBlockMembers.Get(blk->bbInd());
    }

    // Set the byte for "b" to "val" (allocating/extending impPendingBlockMembers if necessary.)
    // Operates on the map in the top-level ancestor.
    void impSetPendingBlockMember(BasicBlock* blk, BYTE val)
    {
        impInlineRoot()->impPendingBlockMembers.Set(blk->bbInd(), val);
    }

    bool impCanReimport;

    bool impSpillStackEntry(unsigned level,
                            unsigned varNum
#ifdef DEBUG
                            ,
                            bool        bAssertOnRecursion,
                            const char* reason
#endif
                            );

    void impSpillStackEnsure(bool spillLeaves = false);
    void impEvalSideEffects();
    void impSpillSpecialSideEff();
    void impSpillSideEffect(bool spillGlobEffects, unsigned chkLevel DEBUGARG(const char* reason));
    void impSpillSideEffects(bool spillGlobEffects, unsigned chkLevel DEBUGARG(const char* reason));
    void impSpillLclRefs(unsigned lclNum, unsigned chkLevel);

    BasicBlock* impPushCatchArgOnStack(BasicBlock* hndBlk, CORINFO_CLASS_HANDLE clsHnd, bool isSingleBlockFilter);

    bool impBlockIsInALoop(BasicBlock* block);
    void impImportBlockCode(BasicBlock* block);

    void impReimportMarkBlock(BasicBlock* block);
    void impReimportMarkSuccessors(BasicBlock* block);

    void impVerifyEHBlock(BasicBlock* block, bool isTryStart);

    void impImportBlockPending(BasicBlock* block);

    // Similar to impImportBlockPending, but assumes that block has already been imported once and is being
    // reimported for some reason.  It specifically does *not* look at verCurrentState to set the EntryState
    // for the block, but instead, just re-uses the block's existing EntryState.
    void impReimportBlockPending(BasicBlock* block);

    var_types impGetByRefResultType(genTreeOps oper, bool fUnsigned, GenTree** pOp1, GenTree** pOp2);

    void impImportBlock(BasicBlock* block);

    // Assumes that "block" is a basic block that completes with a non-empty stack. We will assign the values
    // on the stack to local variables (the "spill temp" variables). The successor blocks will assume that
    // its incoming stack contents are in those locals. This requires "block" and its successors to agree on
    // the variables that will be used -- and for all the predecessors of those successors, and the
    // successors of those predecessors, etc. Call such a set of blocks closed under alternating
    // successor/predecessor edges a "spill clique." A block is a "predecessor" or "successor" member of the
    // clique (or, conceivably, both). Each block has a specified sequence of incoming and outgoing spill
    // temps. If "block" already has its outgoing spill temps assigned (they are always a contiguous series
    // of local variable numbers, so we represent them with the base local variable number), returns that.
    // Otherwise, picks a set of spill temps, and propagates this choice to all blocks in the spill clique of
    // which "block" is a member (asserting, in debug mode, that no block in this clique had its spill temps
    // chosen already. More precisely, that the incoming or outgoing spill temps are not chosen, depending
    // on which kind of member of the clique the block is).
    unsigned impGetSpillTmpBase(BasicBlock* block);

    // Assumes that "block" is a basic block that completes with a non-empty stack. We have previously
    // assigned the values on the stack to local variables (the "spill temp" variables). The successor blocks
    // will assume that its incoming stack contents are in those locals. This requires "block" and its
    // successors to agree on the variables and their types that will be used.  The CLI spec allows implicit
    // conversions between 'int' and 'native int' or 'float' and 'double' stack types. So one predecessor can
    // push an int and another can push a native int.  For 64-bit we have chosen to implement this by typing
    // the "spill temp" as native int, and then importing (or re-importing as needed) so that all the
    // predecessors in the "spill clique" push a native int (sign-extending if needed), and all the
    // successors receive a native int. Similarly float and double are unified to double.
    // This routine is called after a type-mismatch is detected, and it will walk the spill clique to mark
    // blocks for re-importation as appropriate (both successors, so they get the right incoming type, and
    // predecessors, so they insert an upcast if needed).
    void impReimportSpillClique(BasicBlock* block);

    // When we compute a "spill clique" (see above) these byte-maps are allocated to have a byte per basic
    // block, and represent the predecessor and successor members of the clique currently being computed.
    // *** Access to these will need to be locked in a parallel compiler.
    JitExpandArray<BYTE> impSpillCliquePredMembers;
    JitExpandArray<BYTE> impSpillCliqueSuccMembers;

    enum SpillCliqueDir
    {
        SpillCliquePred,
        SpillCliqueSucc
    };

    // Abstract class for receiving a callback while walking a spill clique
    class SpillCliqueWalker
    {
    public:
        virtual void Visit(SpillCliqueDir predOrSucc, BasicBlock* blk) = 0;
    };

    // This class is used for setting the bbStkTempsIn and bbStkTempsOut on the blocks within a spill clique
    class SetSpillTempsBase : public SpillCliqueWalker
    {
        unsigned m_baseTmp;

    public:
        SetSpillTempsBase(unsigned baseTmp) : m_baseTmp(baseTmp)
        {
        }
        virtual void Visit(SpillCliqueDir predOrSucc, BasicBlock* blk);
    };

    // This class is used for implementing impReimportSpillClique part on each block within the spill clique
    class ReimportSpillClique : public SpillCliqueWalker
    {
        Compiler* m_pComp;

    public:
        ReimportSpillClique(Compiler* pComp) : m_pComp(pComp)
        {
        }
        virtual void Visit(SpillCliqueDir predOrSucc, BasicBlock* blk);
    };

    // This is the heart of the algorithm for walking spill cliques. It invokes callback->Visit for each
    // predecessor or successor within the spill clique
    void impWalkSpillCliqueFromPred(BasicBlock* pred, SpillCliqueWalker* callback);

    // For a BasicBlock that has already been imported, the EntryState has an array of GenTrees for the
    // incoming locals. This walks that list an resets the types of the GenTrees to match the types of
    // the VarDscs. They get out of sync when we have int/native int issues (see impReimportSpillClique).
    void impRetypeEntryStateTemps(BasicBlock* blk);

    BYTE impSpillCliqueGetMember(SpillCliqueDir predOrSucc, BasicBlock* blk);
    void impSpillCliqueSetMember(SpillCliqueDir predOrSucc, BasicBlock* blk, BYTE val);

    void impPushVar(GenTree* op, typeInfo tiRetVal);
    GenTreeLclVar* impCreateLocalNode(unsigned lclNum DEBUGARG(IL_OFFSET offset));
    void impLoadVar(unsigned lclNum, IL_OFFSET offset);
    void impLoadArg(unsigned ilArgNum, IL_OFFSET offset);
    void impLoadLoc(unsigned ilLclNum, IL_OFFSET offset);
    bool impReturnInstruction(int prefixFlags, OPCODE& opcode);

#ifdef TARGET_ARM
    void impMarkLclDstNotPromotable(unsigned tmpNum, GenTree* op, CORINFO_CLASS_HANDLE hClass);
#endif

    // A free list of linked list nodes used to represent to-do stacks of basic blocks.
    struct BlockListNode
    {
        BasicBlock*    m_blk;
        BlockListNode* m_next;
        BlockListNode(BasicBlock* blk, BlockListNode* next = nullptr) : m_blk(blk), m_next(next)
        {
        }
        void* operator new(size_t sz, Compiler* comp);
    };
    BlockListNode* impBlockListNodeFreeList;

    void FreeBlockListNode(BlockListNode* node);

    var_types mangleVarArgsType(var_types type);

    regNumber getCallArgIntRegister(regNumber floatReg);
    regNumber getCallArgFloatRegister(regNumber intReg);

    static unsigned jitTotalMethodCompiled;

#ifdef DEBUG
    static LONG jitNestingLevel;
#endif // DEBUG

    static bool impIsInvariant(const GenTree* tree);
    static bool impIsAddressInLocal(const GenTree* tree, GenTree** lclVarTreeOut = nullptr);

    void impMakeDiscretionaryInlineObservations(InlineInfo* pInlineInfo, InlineResult* inlineResult);

    // STATIC inlining decision based on the IL code.
    void impCanInlineIL(CORINFO_METHOD_HANDLE fncHandle,
                        CORINFO_METHOD_INFO*  methInfo,
                        bool                  forceInline,
                        InlineResult*         inlineResult);

    void impCheckCanInline(GenTreeCall*           call,
                           CORINFO_METHOD_HANDLE  fncHandle,
                           unsigned               methAttr,
                           CORINFO_CONTEXT_HANDLE exactContextHnd,
                           InlineCandidateInfo**  ppInlineCandidateInfo,
                           InlineResult*          inlineResult);

    void impInlineRecordArgInfo(InlineInfo* pInlineInfo, CallArg* arg, unsigned argNum, InlineResult* inlineResult);

    void impInlineInitVars(InlineInfo* pInlineInfo);

    unsigned impInlineFetchLocal(unsigned lclNum DEBUGARG(const char* reason));

    GenTree* impInlineFetchArg(unsigned lclNum, InlArgInfo* inlArgInfo, InlLclVarInfo* lclTypeInfo);

    bool impInlineIsThis(GenTree* tree, InlArgInfo* inlArgInfo);

    bool impInlineIsGuaranteedThisDerefBeforeAnySideEffects(GenTree*    additionalTree,
                                                            CallArgs*   additionalCallArgs,
                                                            GenTree*    dereferencedAddress,
                                                            InlArgInfo* inlArgInfo);

    void impMarkInlineCandidate(GenTree*               call,
                                CORINFO_CONTEXT_HANDLE exactContextHnd,
                                bool                   exactContextNeedsRuntimeLookup,
                                CORINFO_CALL_INFO*     callInfo,
                                IL_OFFSET              ilOffset);

    void impMarkInlineCandidateHelper(GenTreeCall*           call,
                                      CORINFO_CONTEXT_HANDLE exactContextHnd,
                                      bool                   exactContextNeedsRuntimeLookup,
                                      CORINFO_CALL_INFO*     callInfo,
                                      IL_OFFSET              ilOffset);

    bool impTailCallRetTypeCompatible(bool                     allowWidening,
                                      var_types                callerRetType,
                                      CORINFO_CLASS_HANDLE     callerRetTypeClass,
                                      CorInfoCallConvExtension callerCallConv,
                                      var_types                calleeRetType,
                                      CORINFO_CLASS_HANDLE     calleeRetTypeClass,
                                      CorInfoCallConvExtension calleeCallConv);

    bool impIsTailCallILPattern(
        bool tailPrefixed, OPCODE curOpcode, const BYTE* codeAddrOfNextOpcode, const BYTE* codeEnd, bool isRecursive);

    bool impIsImplicitTailCallCandidate(
        OPCODE curOpcode, const BYTE* codeAddrOfNextOpcode, const BYTE* codeEnd, int prefixFlags, bool isRecursive);

    bool impIsClassExact(CORINFO_CLASS_HANDLE classHnd);
    bool impCanSkipCovariantStoreCheck(GenTree* value, GenTree* array);

    methodPointerInfo* impAllocateMethodPointerInfo(const CORINFO_RESOLVED_TOKEN& token, mdToken tokenConstrained);

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX                           FlowGraph                                       XX
    XX                                                                           XX
    XX   Info about the basic-blocks, their contents and the flow analysis       XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */

public:
    BasicBlock* fgFirstBB;        // Beginning of the basic block list
    BasicBlock* fgLastBB;         // End of the basic block list
    BasicBlock* fgFirstColdBlock; // First block to be placed in the cold section
    BasicBlock* fgEntryBB;        // For OSR, the original method's entry point
    BasicBlock* fgOSREntryBB;     // For OSR, the logical entry point (~ patchpoint)
#if defined(FEATURE_EH_FUNCLETS)
    BasicBlock* fgFirstFuncletBB; // First block of outlined funclets (to allow block insertion before the funclets)
#endif
    BasicBlock* fgFirstBBScratch;   // Block inserted for initialization stuff. Is nullptr if no such block has been
                                    // created.
    BasicBlockList* fgReturnBlocks; // list of BBJ_RETURN blocks
    unsigned        fgEdgeCount;    // # of control flow edges between the BBs
    unsigned        fgBBcount;      // # of BBs in the method
#ifdef DEBUG
    unsigned                     fgBBcountAtCodegen; // # of BBs in the method at the start of codegen
    jitstd::vector<BasicBlock*>* fgBBOrder;          // ordered vector of BBs
#endif
    unsigned     fgBBNumMax;       // The max bbNum that has been assigned to basic blocks
    unsigned     fgDomBBcount;     // # of BBs for which we have dominator and reachability information
    BasicBlock** fgBBInvPostOrder; // The flow graph stored in an array sorted in topological order, needed to compute
                                   // dominance. Indexed by block number. Size: fgBBNumMax + 1.

    // After the dominance tree is computed, we cache a DFS preorder number and DFS postorder number to compute
    // dominance queries in O(1). fgDomTreePreOrder and fgDomTreePostOrder are arrays giving the block's preorder and
    // postorder number, respectively. The arrays are indexed by basic block number. (Note that blocks are numbered
    // starting from one. Thus, we always waste element zero. This makes debugging easier and makes the code less likely
    // to suffer from bugs stemming from forgetting to add or subtract one from the block number to form an array
    // index). The arrays are of size fgBBNumMax + 1.
    unsigned* fgDomTreePreOrder;
    unsigned* fgDomTreePostOrder;

    // Dominator tree used by SSA construction and copy propagation (the two are expected to use the same tree
    // in order to avoid the need for SSA reconstruction and an "out of SSA" phase).
    DomTreeNode* fgSsaDomTree;

    bool fgBBVarSetsInited;

    // Allocate array like T* a = new T[fgBBNumMax + 1];
    // Using helper so we don't keep forgetting +1.
    template <typename T>
    T* fgAllocateTypeForEachBlk(CompMemKind cmk = CMK_Unknown)
    {
        return getAllocator(cmk).allocate<T>(fgBBNumMax + 1);
    }

    // BlockSets are relative to a specific set of BasicBlock numbers. If that changes
    // (if the blocks are renumbered), this changes. BlockSets from different epochs
    // cannot be meaningfully combined. Note that new blocks can be created with higher
    // block numbers without changing the basic block epoch. These blocks *cannot*
    // participate in a block set until the blocks are all renumbered, causing the epoch
    // to change. This is useful if continuing to use previous block sets is valuable.
    // If the epoch is zero, then it is uninitialized, and block sets can't be used.
    unsigned fgCurBBEpoch;

    unsigned GetCurBasicBlockEpoch()
    {
        return fgCurBBEpoch;
    }

    // The number of basic blocks in the current epoch. When the blocks are renumbered,
    // this is fgBBcount. As blocks are added, fgBBcount increases, fgCurBBEpochSize remains
    // the same, until a new BasicBlock epoch is created, such as when the blocks are all renumbered.
    unsigned fgCurBBEpochSize;

    // The number of "size_t" elements required to hold a bitset large enough for fgCurBBEpochSize
    // bits. This is precomputed to avoid doing math every time BasicBlockBitSetTraits::GetArrSize() is called.
    unsigned fgBBSetCountInSizeTUnits;

    void NewBasicBlockEpoch()
    {
        INDEBUG(unsigned oldEpochArrSize = fgBBSetCountInSizeTUnits);

        // We have a new epoch. Compute and cache the size needed for new BlockSets.
        fgCurBBEpoch++;
        fgCurBBEpochSize = fgBBNumMax + 1;
        fgBBSetCountInSizeTUnits =
            roundUp(fgCurBBEpochSize, (unsigned)(sizeof(size_t) * 8)) / unsigned(sizeof(size_t) * 8);

#ifdef DEBUG
        // All BlockSet objects are now invalid!
        fgReachabilitySetsValid = false; // the bbReach sets are now invalid!
        fgEnterBlksSetValid     = false; // the fgEnterBlks set is now invalid!

        if (verbose)
        {
            unsigned epochArrSize = BasicBlockBitSetTraits::GetArrSize(this);
            printf("\nNew BlockSet epoch %d, # of blocks (including unused BB00): %u, bitset array size: %u (%s)",
                   fgCurBBEpoch, fgCurBBEpochSize, epochArrSize, (epochArrSize <= 1) ? "short" : "long");
            if ((fgCurBBEpoch != 1) && ((oldEpochArrSize <= 1) != (epochArrSize <= 1)))
            {
                // If we're not just establishing the first epoch, and the epoch array size has changed such that we're
                // going to change our bitset representation from short (just a size_t bitset) to long (a pointer to an
                // array of size_t bitsets), then print that out.
                printf("; NOTE: BlockSet size was previously %s!", (oldEpochArrSize <= 1) ? "short" : "long");
            }
            printf("\n");
        }
#endif // DEBUG
    }

    void EnsureBasicBlockEpoch()
    {
        if (fgCurBBEpochSize != fgBBNumMax + 1)
        {
            NewBasicBlockEpoch();
        }
    }

    BasicBlock* fgNewBasicBlock(BBjumpKinds jumpKind);
    bool fgEnsureFirstBBisScratch();
    bool fgFirstBBisScratch();
    bool fgBBisScratch(BasicBlock* block);

    void fgExtendEHRegionBefore(BasicBlock* block);
    void fgExtendEHRegionAfter(BasicBlock* block);

    BasicBlock* fgNewBBbefore(BBjumpKinds jumpKind, BasicBlock* block, bool extendRegion);

    BasicBlock* fgNewBBafter(BBjumpKinds jumpKind, BasicBlock* block, bool extendRegion);

    BasicBlock* fgNewBBinRegion(BBjumpKinds jumpKind,
                                unsigned    tryIndex,
                                unsigned    hndIndex,
                                BasicBlock* nearBlk,
                                bool        putInFilter = false,
                                bool        runRarely   = false,
                                bool        insertAtEnd = false);

    BasicBlock* fgNewBBinRegion(BBjumpKinds jumpKind,
                                BasicBlock* srcBlk,
                                bool        runRarely   = false,
                                bool        insertAtEnd = false);

    BasicBlock* fgNewBBinRegion(BBjumpKinds jumpKind);

    BasicBlock* fgNewBBinRegionWorker(BBjumpKinds jumpKind,
                                      BasicBlock* afterBlk,
                                      unsigned    xcptnIndex,
                                      bool        putInTryRegion);

    void fgInsertBBbefore(BasicBlock* insertBeforeBlk, BasicBlock* newBlk);
    void fgInsertBBafter(BasicBlock* insertAfterBlk, BasicBlock* newBlk);
    void fgUnlinkBlock(BasicBlock* block);

#ifdef FEATURE_JIT_METHOD_PERF
    unsigned fgMeasureIR();
#endif // FEATURE_JIT_METHOD_PERF

    bool fgModified;             // True if the flow graph has been modified recently
    bool fgComputePredsDone;     // Have we computed the bbPreds list
    bool fgCheapPredsValid;      // Is the bbCheapPreds list valid?
    bool fgDomsComputed;         // Have we computed the dominator sets?
    bool fgReturnBlocksComputed; // Have we computed the return blocks list?
    bool fgOptimizedFinally;     // Did we optimize any try-finallys?

    bool fgHasSwitch; // any BBJ_SWITCH jumps?

    BlockSet fgEnterBlks; // Set of blocks which have a special transfer of control; the "entry" blocks plus EH handler
                          // begin blocks.
#if defined(FEATURE_EH_FUNCLETS) && defined(TARGET_ARM)
    BlockSet fgAlwaysBlks; // Set of blocks which are BBJ_ALWAYS part  of BBJ_CALLFINALLY/BBJ_ALWAYS pair that should
                           // never be removed due to a requirement to use the BBJ_ALWAYS for generating code and
                           // not have "retless" blocks.

#endif // defined(FEATURE_EH_FUNCLETS) && defined(TARGET_ARM)

#ifdef DEBUG
    bool fgReachabilitySetsValid; // Are the bbReach sets valid?
    bool fgEnterBlksSetValid;     // Is the fgEnterBlks set valid?
#endif                            // DEBUG

    bool fgRemoveRestOfBlock; // true if we know that we will throw
    bool fgStmtRemoved;       // true if we remove statements -> need new DFA

    // There are two modes for ordering of the trees.
    //  - In FGOrderTree, the dominant ordering is the tree order, and the nodes contained in
    //    each tree and sub-tree are contiguous, and can be traversed (in gtNext/gtPrev order)
    //    by traversing the tree according to the order of the operands.
    //  - In FGOrderLinear, the dominant ordering is the linear order.

    enum FlowGraphOrder
    {
        FGOrderTree,
        FGOrderLinear
    };
    FlowGraphOrder fgOrder;

    // The following are boolean flags that keep track of the state of internal data structures

    bool     fgStmtListThreaded;       // true if the node list is now threaded
    bool     fgCanRelocateEHRegions;   // true if we are allowed to relocate the EH regions
    bool     fgEdgeWeightsComputed;    // true after we have called fgComputeEdgeWeights
    bool     fgHaveValidEdgeWeights;   // true if we were successful in computing all of the edge weights
    bool     fgSlopUsedInEdgeWeights;  // true if their was some slop used when computing the edge weights
    bool     fgRangeUsedInEdgeWeights; // true if some of the edgeWeight are expressed in Min..Max form
    weight_t fgCalledCount;            // count of the number of times this method was called
                                       // This is derived from the profile data
                                       // or is BB_UNITY_WEIGHT when we don't have profile data

#if defined(FEATURE_EH_FUNCLETS)
    bool fgFuncletsCreated; // true if the funclet creation phase has been run
#endif                      // FEATURE_EH_FUNCLETS

    bool fgGlobalMorph; // indicates if we are during the global morphing phase
                        // since fgMorphTree can be called from several places

    bool     impBoxTempInUse; // the temp below is valid and available
    unsigned impBoxTemp;      // a temporary that is used for boxing

#ifdef DEBUG
    bool jitFallbackCompile; // Are we doing a fallback compile? That is, have we executed a NO_WAY assert,
                             //   and we are trying to compile again in a "safer", minopts mode?
#endif

#if defined(DEBUG)
    unsigned impInlinedCodeSize;
    bool     fgPrintInlinedMethods;
#endif

    jitstd::vector<flowList*>* fgPredListSortVector;

    //-------------------------------------------------------------------------

    void fgInit();

    PhaseStatus fgImport();

    PhaseStatus fgTransformIndirectCalls();

    PhaseStatus fgTransformPatchpoints();

    PhaseStatus fgMorphInit();

    PhaseStatus fgInline();

    PhaseStatus fgRemoveEmptyTry();

    PhaseStatus fgRemoveEmptyFinally();

    PhaseStatus fgMergeFinallyChains();

    PhaseStatus fgCloneFinally();

    void fgCleanupContinuation(BasicBlock* continuation);

#if defined(FEATURE_EH_FUNCLETS) && defined(TARGET_ARM)

    PhaseStatus fgUpdateFinallyTargetFlags();

    void fgClearAllFinallyTargetBits();

    void fgAddFinallyTargetFlags();

#endif // defined(FEATURE_EH_FUNCLETS) && defined(TARGET_ARM)

    PhaseStatus fgTailMergeThrows();
    void fgTailMergeThrowsFallThroughHelper(BasicBlock* predBlock,
                                            BasicBlock* nonCanonicalBlock,
                                            BasicBlock* canonicalBlock,
                                            flowList*   predEdge);
    void fgTailMergeThrowsJumpToHelper(BasicBlock* predBlock,
                                       BasicBlock* nonCanonicalBlock,
                                       BasicBlock* canonicalBlock,
                                       flowList*   predEdge);

#if defined(FEATURE_EH_FUNCLETS) && defined(TARGET_ARM)
    // Sometimes we need to defer updating the BBF_FINALLY_TARGET bit. fgNeedToAddFinallyTargetBits signals
    // when this is necessary.
    bool fgNeedToAddFinallyTargetBits;
#endif // defined(FEATURE_EH_FUNCLETS) && defined(TARGET_ARM)

    bool fgRetargetBranchesToCanonicalCallFinally(BasicBlock*      block,
                                                  BasicBlock*      handler,
                                                  BlockToBlockMap& continuationMap);

    GenTree* fgGetCritSectOfStaticMethod();

#if defined(FEATURE_EH_FUNCLETS)

    void fgAddSyncMethodEnterExit();

    GenTree* fgCreateMonitorTree(unsigned lvaMonitorBool, unsigned lvaThisVar, BasicBlock* block, bool enter);

    void fgConvertSyncReturnToLeave(BasicBlock* block);

#endif // FEATURE_EH_FUNCLETS

    void fgAddReversePInvokeEnterExit();

    bool fgMoreThanOneReturnBlock();

    // The number of separate return points in the method.
    unsigned fgReturnCount;

    PhaseStatus fgAddInternal();

    enum class FoldResult
    {
        FOLD_DID_NOTHING,
        FOLD_CHANGED_CONTROL_FLOW,
        FOLD_REMOVED_LAST_STMT,
        FOLD_ALTERED_LAST_STMT,
    };

    FoldResult fgFoldConditional(BasicBlock* block);

    void fgMorphStmts(BasicBlock* block);
    void fgMorphBlocks();

    void fgMergeBlockReturn(BasicBlock* block);

    bool fgMorphBlockStmt(BasicBlock* block, Statement* stmt DEBUGARG(const char* msg));

    //------------------------------------------------------------------------------------------------------------
    // MorphMDArrayTempCache: a simple cache of compiler temporaries in the local variable table, used to minimize
    // the number of locals allocated when doing early multi-dimensional array operation expansion. Two types of
    // temps are created and cached (due to the two types of temps needed by the MD array expansion): TYP_INT and
    // TYP_REF. `GrabTemp` either returns an available temp from the cache or allocates a new temp and returns it
    // after adding it to the cache. `Reset` makes all the temps in the cache available for subsequent re-use.
    //
    class MorphMDArrayTempCache
    {
    private:
        class TempList
        {
        public:
            TempList(Compiler* compiler)
                : m_compiler(compiler), m_first(nullptr), m_insertPtr(&m_first), m_nextAvail(nullptr)
            {
            }

            unsigned GetTemp();

            void Reset()
            {
                m_nextAvail = m_first;
            }

        private:
            struct Node
            {
                Node(unsigned tmp) : next(nullptr), tmp(tmp)
                {
                }

                Node*    next;
                unsigned tmp;
            };

            Compiler* m_compiler;
            Node*     m_first;
            Node**    m_insertPtr;
            Node*     m_nextAvail;
        };

        TempList intTemps; // Temps for genActualType() == TYP_INT
        TempList refTemps; // Temps for TYP_REF

    public:
        MorphMDArrayTempCache(Compiler* compiler) : intTemps(compiler), refTemps(compiler)
        {
        }

        unsigned GrabTemp(var_types type);

        void Reset()
        {
            intTemps.Reset();
            refTemps.Reset();
        }
    };

    bool fgMorphArrayOpsStmt(MorphMDArrayTempCache* pTempCache, BasicBlock* block, Statement* stmt);
    PhaseStatus fgMorphArrayOps();

    void fgSetOptions();

#ifdef DEBUG
    static fgWalkPreFn fgAssertNoQmark;
    void fgPreExpandQmarkChecks(GenTree* expr);
    void        fgPostExpandQmarkChecks();
    static void fgCheckQmarkAllowedForm(GenTree* tree);
#endif

    IL_OFFSET fgFindBlockILOffset(BasicBlock* block);
    void fgFixEntryFlowForOSR();

    BasicBlock* fgSplitBlockAtBeginning(BasicBlock* curr);
    BasicBlock* fgSplitBlockAtEnd(BasicBlock* curr);
    BasicBlock* fgSplitBlockAfterStatement(BasicBlock* curr, Statement* stmt);
    BasicBlock* fgSplitBlockAfterNode(BasicBlock* curr, GenTree* node); // for LIR
    BasicBlock* fgSplitEdge(BasicBlock* curr, BasicBlock* succ);

    Statement* fgNewStmtFromTree(GenTree* tree, BasicBlock* block, const DebugInfo& di);
    Statement* fgNewStmtFromTree(GenTree* tree);
    Statement* fgNewStmtFromTree(GenTree* tree, BasicBlock* block);
    Statement* fgNewStmtFromTree(GenTree* tree, const DebugInfo& di);

    GenTree* fgGetTopLevelQmark(GenTree* expr, GenTree** ppDst = nullptr);
    void fgExpandQmarkForCastInstOf(BasicBlock* block, Statement* stmt);
    void fgExpandQmarkStmt(BasicBlock* block, Statement* stmt);
    void fgExpandQmarkNodes();

    // Do "simple lowering."  This functionality is (conceptually) part of "general"
    // lowering that is distributed between fgMorph and the lowering phase of LSRA.
    PhaseStatus fgSimpleLowering();

#if FEATURE_LOOP_ALIGN
    PhaseStatus placeLoopAlignInstructions();
#endif

    GenTree* fgInitThisClass();

    GenTreeCall* fgGetStaticsCCtorHelper(CORINFO_CLASS_HANDLE cls, CorInfoHelpFunc helper);

    GenTreeCall* fgGetSharedCCtor(CORINFO_CLASS_HANDLE cls);

    bool backendRequiresLocalVarLifetimes()
    {
        return !opts.MinOpts() || m_pLinearScan->willEnregisterLocalVars();
    }

    void fgLocalVarLiveness();

    void fgLocalVarLivenessInit();

    void fgPerNodeLocalVarLiveness(GenTree* node);
    void fgPerBlockLocalVarLiveness();

    VARSET_VALRET_TP fgGetHandlerLiveVars(BasicBlock* block);

    void fgLiveVarAnalysis(bool updateInternalOnly = false);

    void fgComputeLifeCall(VARSET_TP& life, GenTreeCall* call);

    void fgComputeLifeTrackedLocalUse(VARSET_TP& life, LclVarDsc& varDsc, GenTreeLclVarCommon* node);
    bool fgComputeLifeTrackedLocalDef(VARSET_TP&           life,
                                      VARSET_VALARG_TP     keepAliveVars,
                                      LclVarDsc&           varDsc,
                                      GenTreeLclVarCommon* node);
    bool fgComputeLifeUntrackedLocal(VARSET_TP&           life,
                                     VARSET_VALARG_TP     keepAliveVars,
                                     LclVarDsc&           varDsc,
                                     GenTreeLclVarCommon* lclVarNode);
    bool fgComputeLifeLocal(VARSET_TP& life, VARSET_VALARG_TP keepAliveVars, GenTree* lclVarNode);

    void fgComputeLife(VARSET_TP&       life,
                       GenTree*         startNode,
                       GenTree*         endNode,
                       VARSET_VALARG_TP volatileVars,
                       bool* pStmtInfoDirty DEBUGARG(bool* treeModf));

    void fgComputeLifeLIR(VARSET_TP& life, BasicBlock* block, VARSET_VALARG_TP volatileVars);

    bool fgTryRemoveNonLocal(GenTree* node, LIR::Range* blockRange);

    bool fgTryRemoveDeadStoreLIR(GenTree* store, GenTreeLclVarCommon* lclNode, BasicBlock* block);

    bool fgRemoveDeadStore(GenTree**        pTree,
                           LclVarDsc*       varDsc,
                           VARSET_VALARG_TP life,
                           bool*            doAgain,
                           bool*            pStmtInfoDirty,
                           bool* pStoreRemoved DEBUGARG(bool* treeModf));

    void fgInterBlockLocalVarLiveness();

    // Blocks: convenience methods for enabling range-based `for` iteration over the function's blocks, e.g.:
    // 1.   for (BasicBlock* const block : compiler->Blocks()) ...
    // 2.   for (BasicBlock* const block : compiler->Blocks(startBlock)) ...
    // 3.   for (BasicBlock* const block : compiler->Blocks(startBlock, endBlock)) ...
    // In case (1), the block list can be empty. In case (2), `startBlock` can be nullptr. In case (3),
    // both `startBlock` and `endBlock` must be non-null.
    //
    BasicBlockSimpleList Blocks() const
    {
        return BasicBlockSimpleList(fgFirstBB);
    }

    BasicBlockSimpleList Blocks(BasicBlock* startBlock) const
    {
        return BasicBlockSimpleList(startBlock);
    }

    BasicBlockRangeList Blocks(BasicBlock* startBlock, BasicBlock* endBlock) const
    {
        return BasicBlockRangeList(startBlock, endBlock);
    }

    // This array, managed by the SSA numbering infrastructure, keeps "outlined composite SSA numbers".
    // See "SsaNumInfo::GetNum" for more details on when this is needed.
    JitExpandArrayStack<unsigned>* m_outlinedCompositeSsaNums;

    // This map tracks nodes whose value numbers explicitly or implicitly depend on memory states.
    // The map provides the entry block of the most closely enclosing loop that
    // defines the memory region accessed when defining the nodes's VN.
    //
    // This information should be consulted when considering hoisting node out of a loop, as the VN
    // for the node will only be valid within the indicated loop.
    //
    // It is not fine-grained enough to track memory dependence within loops, so cannot be used
    // for more general code motion.
    //
    // If a node does not have an entry in the map we currently assume the VN is not memory dependent
    // and so memory does not constrain hoisting.
    //
    typedef JitHashTable<GenTree*, JitPtrKeyFuncs<GenTree>, BasicBlock*> NodeToLoopMemoryBlockMap;
    NodeToLoopMemoryBlockMap* m_nodeToLoopMemoryBlockMap;
    NodeToLoopMemoryBlockMap* GetNodeToLoopMemoryBlockMap()
    {
        if (m_nodeToLoopMemoryBlockMap == nullptr)
        {
            m_nodeToLoopMemoryBlockMap = new (getAllocator()) NodeToLoopMemoryBlockMap(getAllocator());
        }
        return m_nodeToLoopMemoryBlockMap;
    }

    void optRecordLoopMemoryDependence(GenTree* tree, BasicBlock* block, ValueNum memoryVN);
    void optCopyLoopMemoryDependence(GenTree* fromTree, GenTree* toTree);

    inline bool PreciseRefCountsRequired();

    // Performs SSA conversion.
    PhaseStatus fgSsaBuild();

    // Reset any data structures to the state expected by "fgSsaBuild", so it can be run again.
    void fgResetForSsa();

    unsigned fgSsaPassesCompleted; // Number of times fgSsaBuild has been run.
    bool     fgSsaChecksEnabled;   // True if SSA info can be cross-checked versus IR

#ifdef DEBUG
    void DumpSsaSummary();
#endif

    // Returns "true" if this is a special variable that is never zero initialized in the prolog.
    inline bool fgVarIsNeverZeroInitializedInProlog(unsigned varNum);

    // Returns "true" if the variable needs explicit zero initialization.
    inline bool fgVarNeedsExplicitZeroInit(unsigned varNum, bool bbInALoop, bool bbIsReturn);

    // The value numbers for this compilation.
    ValueNumStore* vnStore;

public:
    ValueNumStore* GetValueNumStore()
    {
        return vnStore;
    }

    // Do value numbering (assign a value number to each
    // tree node).
    PhaseStatus fgValueNumber();

    void fgValueNumberLocalStore(GenTree*             storeNode,
                                 GenTreeLclVarCommon* lclDefNode,
                                 ssize_t              offset,
                                 unsigned             storeSize,
                                 ValueNumPair         value,
                                 bool                 normalize = true);

    void fgValueNumberArrayElemLoad(GenTree* loadTree, VNFuncApp* addrFunc);

    void fgValueNumberArrayElemStore(GenTree* storeNode, VNFuncApp* addrFunc, unsigned storeSize, ValueNum value);

    void fgValueNumberFieldLoad(GenTree* loadTree, GenTree* baseAddr, FieldSeq* fieldSeq, ssize_t offset);

    void fgValueNumberFieldStore(
        GenTree* storeNode, GenTree* baseAddr, FieldSeq* fieldSeq, ssize_t offset, unsigned storeSize, ValueNum value);

    // Compute the value number for a byref-exposed load of the given type via the given pointerVN.
    ValueNum fgValueNumberByrefExposedLoad(var_types type, ValueNum pointerVN);

    unsigned fgVNPassesCompleted; // Number of times fgValueNumber has been run.

    // Utility functions for fgValueNumber.

    // Perform value-numbering for the trees in "blk".
    void fgValueNumberBlock(BasicBlock* blk);

    // Requires that "entryBlock" is the entry block of loop "loopNum", and that "loopNum" is the
    // innermost loop of which "entryBlock" is the entry.  Returns the value number that should be
    // assumed for the memoryKind at the start "entryBlk".
    ValueNum fgMemoryVNForLoopSideEffects(MemoryKind memoryKind, BasicBlock* entryBlock, unsigned loopNum);

    // Called when an operation (performed by "tree", described by "msg") may cause the GcHeap to be mutated.
    // As GcHeap is a subset of ByrefExposed, this will also annotate the ByrefExposed mutation.
    void fgMutateGcHeap(GenTree* tree DEBUGARG(const char* msg));

    // Called when an operation (performed by "tree", described by "msg") may cause an address-exposed local to be
    // mutated.
    void fgMutateAddressExposedLocal(GenTree* tree DEBUGARG(const char* msg));

    // For a GC heap store at curTree, record the new curMemoryVN's and update curTree's MemorySsaMap.
    // As GcHeap is a subset of ByrefExposed, this will also record the ByrefExposed store.
    void recordGcHeapStore(GenTree* curTree, ValueNum gcHeapVN DEBUGARG(const char* msg));

    // For a store to an address-exposed local at curTree, record the new curMemoryVN and update curTree's MemorySsaMap.
    void recordAddressExposedLocalStore(GenTree* curTree, ValueNum memoryVN DEBUGARG(const char* msg));

    void fgSetCurrentMemoryVN(MemoryKind memoryKind, ValueNum newMemoryVN);

    // Tree caused an update in the current memory VN.  If "tree" has an associated heap SSA #, record that
    // value in that SSA #.
    void fgValueNumberRecordMemorySsa(MemoryKind memoryKind, GenTree* tree);

    // The input 'tree' is a leaf node that is a constant
    // Assign the proper value number to the tree
    void fgValueNumberTreeConst(GenTree* tree);

    // If the VN store has been initialized, reassign the
    // proper value number to the constant tree.
    void fgUpdateConstTreeValueNumber(GenTree* tree);

    // Assumes that all inputs to "tree" have had value numbers assigned; assigns a VN to tree.
    // (With some exceptions: the VN of the lhs of an assignment is assigned as part of the
    // assignment.)
    void fgValueNumberTree(GenTree* tree);

    void fgValueNumberAssignment(GenTreeOp* tree);

    // Does value-numbering for a block assignment.
    void fgValueNumberBlockAssignment(GenTree* tree);

    // Does value-numbering for a variable definition that has SSA.
    void fgValueNumberSsaVarDef(GenTreeLclVarCommon* lcl);

    // Does value-numbering for a cast tree.
    void fgValueNumberCastTree(GenTree* tree);

    // Does value-numbering for a bitcast tree.
    void fgValueNumberBitCast(GenTree* tree);

    // Does value-numbering for an intrinsic tree.
    void fgValueNumberIntrinsic(GenTree* tree);

    void fgValueNumberArrIndexAddr(GenTreeArrAddr* arrAddr);

#ifdef FEATURE_SIMD
    // Does value-numbering for a GT_SIMD tree
    void fgValueNumberSimd(GenTreeSIMD* tree);
#endif // FEATURE_SIMD

#ifdef FEATURE_HW_INTRINSICS
    // Does value-numbering for a GT_HWINTRINSIC tree
    void fgValueNumberHWIntrinsic(GenTreeHWIntrinsic* tree);
#endif // FEATURE_HW_INTRINSICS

    // Does value-numbering for a call.  We interpret some helper calls.
    void fgValueNumberCall(GenTreeCall* call);

    // Does value-numbering for a helper representing a cast operation.
    void fgValueNumberCastHelper(GenTreeCall* call);

    // Does value-numbering for a helper "call" that has a VN function symbol "vnf".
    void fgValueNumberHelperCallFunc(GenTreeCall* call, VNFunc vnf, ValueNumPair vnpExc);

    // Requires "helpCall" to be a helper call.  Assigns it a value number;
    // we understand the semantics of some of the calls.  Returns "true" if
    // the call may modify the heap (we assume arbitrary memory side effects if so).
    bool fgValueNumberHelperCall(GenTreeCall* helpCall);

    // Requires that "helpFunc" is one of the pure Jit Helper methods.
    // Returns the corresponding VNFunc to use for value numbering
    VNFunc fgValueNumberJitHelperMethodVNFunc(CorInfoHelpFunc helpFunc);

    // Adds the exception set for the current tree node which has a memory indirection operation
    void fgValueNumberAddExceptionSetForIndirection(GenTree* tree, GenTree* baseAddr);

    // Adds the exception sets for the current tree node which is performing a division or modulus operation
    void fgValueNumberAddExceptionSetForDivision(GenTree* tree);

    // Adds the exception set for the current tree node which is performing a overflow checking operation
    void fgValueNumberAddExceptionSetForOverflow(GenTree* tree);

    // Adds the exception set for the current tree node which is performing a bounds check operation
    void fgValueNumberAddExceptionSetForBoundsCheck(GenTree* tree);

    // Adds the exception set for the current tree node which is performing a ckfinite operation
    void fgValueNumberAddExceptionSetForCkFinite(GenTree* tree);

    // Adds the exception sets for the current tree node
    void fgValueNumberAddExceptionSet(GenTree* tree);

#ifdef DEBUG
    void fgDebugCheckExceptionSets();
#endif

    // These are the current value number for the memory implicit variables while
    // doing value numbering.  These are the value numbers under the "liberal" interpretation
    // of memory values; the "conservative" interpretation needs no VN, since every access of
    // memory yields an unknown value.
    ValueNum fgCurMemoryVN[MemoryKindCount];

    // Return a "pseudo"-class handle for an array element type.  If "elemType" is TYP_STRUCT,
    // requires "elemStructType" to be non-null (and to have a low-order zero).  Otherwise, low order bit
    // is 1, and the rest is an encoding of "elemTyp".
    static CORINFO_CLASS_HANDLE EncodeElemType(var_types elemTyp, CORINFO_CLASS_HANDLE elemStructType)
    {
        if (elemStructType != nullptr)
        {
            assert(varTypeIsStruct(elemTyp) || elemTyp == TYP_REF || elemTyp == TYP_BYREF ||
                   varTypeIsIntegral(elemTyp));
            assert((size_t(elemStructType) & 0x1) == 0x0); // Make sure the encoding below is valid.
            return elemStructType;
        }
        else
        {
            assert(elemTyp != TYP_STRUCT);
            elemTyp = varTypeToSigned(elemTyp);
            return CORINFO_CLASS_HANDLE(size_t(elemTyp) << 1 | 0x1);
        }
    }
    // If "clsHnd" is the result of an "EncodePrim" call, returns true and sets "*pPrimType" to the
    // var_types it represents.  Otherwise, returns TYP_STRUCT (on the assumption that "clsHnd" is
    // the struct type of the element).
    static var_types DecodeElemType(CORINFO_CLASS_HANDLE clsHnd)
    {
        size_t clsHndVal = size_t(clsHnd);
        if (clsHndVal & 0x1)
        {
            return var_types(clsHndVal >> 1);
        }
        else
        {
            return TYP_STRUCT;
        }
    }

    // Convert a BYTE which represents the VM's CorInfoGCtype to the JIT's var_types
    var_types getJitGCType(BYTE gcType);

    // Returns true if the provided type should be treated as a primitive type
    // for the unmanaged calling conventions.
    bool isNativePrimitiveStructType(CORINFO_CLASS_HANDLE clsHnd);

    enum structPassingKind
    {
        SPK_Unknown,       // Invalid value, never returned
        SPK_PrimitiveType, // The struct is passed/returned using a primitive type.
        SPK_EnclosingType, // Like SPK_Primitive type, but used for return types that
                           //  require a primitive type temp that is larger than the struct size.
                           //  Currently used for structs of size 3, 5, 6, or 7 bytes.
        SPK_ByValue,       // The struct is passed/returned by value (using the ABI rules)
                           //  for ARM64 and UNIX_X64 in multiple registers. (when all of the
                           //   parameters registers are used, then the stack will be used)
                           //  for X86 passed on the stack, for ARM32 passed in registers
                           //   or the stack or split between registers and the stack.
        SPK_ByValueAsHfa,  // The struct is passed/returned as an HFA in multiple registers.
        SPK_ByReference
    }; // The struct is passed/returned by reference to a copy/buffer.

    // Get the "primitive" type that is used when we are given a struct of size 'structSize'.
    // For pointer sized structs the 'clsHnd' is used to determine if the struct contains GC ref.
    // A "primitive" type is one of the scalar types: byte, short, int, long, ref, float, double
    // If we can't or shouldn't use a "primitive" type then TYP_UNKNOWN is returned.
    //
    // isVarArg is passed for use on Windows Arm64 to change the decision returned regarding
    // hfa types.
    //
    var_types getPrimitiveTypeForStruct(unsigned structSize, CORINFO_CLASS_HANDLE clsHnd, bool isVarArg);

    // Get the type that is used to pass values of the given struct type.
    // isVarArg is passed for use on Windows Arm64 to change the decision returned regarding
    // hfa types.
    //
    var_types getArgTypeForStruct(CORINFO_CLASS_HANDLE clsHnd,
                                  structPassingKind*   wbPassStruct,
                                  bool                 isVarArg,
                                  unsigned             structSize);

    // Get the type that is used to return values of the given struct type.
    // If the size is unknown, pass 0 and it will be determined from 'clsHnd'.
    var_types getReturnTypeForStruct(CORINFO_CLASS_HANDLE     clsHnd,
                                     CorInfoCallConvExtension callConv,
                                     structPassingKind*       wbPassStruct = nullptr,
                                     unsigned                 structSize   = 0);

#ifdef DEBUG
    // Print a representation of "vnp" or "vn" on standard output.
    // If "level" is non-zero, we also print out a partial expansion of the value.
    void vnpPrint(ValueNumPair vnp, unsigned level);
    void vnPrint(ValueNum vn, unsigned level);
#endif

    bool fgDominate(BasicBlock* b1, BasicBlock* b2); // Return true if b1 dominates b2

    // Dominator computation member functions
    // Not exposed outside Compiler
protected:
    bool fgReachable(BasicBlock* b1, BasicBlock* b2); // Returns true if block b1 can reach block b2

    // Compute immediate dominators, the dominator tree and and its pre/post-order travsersal numbers.
    void fgComputeDoms();

    void fgCompDominatedByExceptionalEntryBlocks();

    BlockSet_ValRet_T fgGetDominatorSet(BasicBlock* block); // Returns a set of blocks that dominate the given block.
    // Note: this is relatively slow compared to calling fgDominate(),
    // especially if dealing with a single block versus block check.

    void fgComputeReachabilitySets(); // Compute bbReach sets. (Also sets BBF_GC_SAFE_POINT flag on blocks.)

    void fgComputeReturnBlocks(); // Initialize fgReturnBlocks to a list of BBJ_RETURN blocks.

    void fgComputeEnterBlocksSet(); // Compute the set of entry blocks, 'fgEnterBlks'.

    // Remove blocks determined to be unreachable by the 'canRemoveBlock'.
    template <typename CanRemoveBlockBody>
    bool fgRemoveUnreachableBlocks(CanRemoveBlockBody canRemoveBlock);

    PhaseStatus fgComputeReachability(); // Perform flow graph node reachability analysis.

    bool fgRemoveDeadBlocks(); // Identify and remove dead blocks.

    BasicBlock* fgIntersectDom(BasicBlock* a, BasicBlock* b); // Intersect two immediate dominator sets.

    void fgDfsInvPostOrder(); // In order to compute dominance using fgIntersectDom, the flow graph nodes must be
                              // processed in topological sort, this function takes care of that.

    void fgDfsInvPostOrderHelper(BasicBlock* block, BlockSet& visited, unsigned* count);

    BlockSet_ValRet_T fgDomFindStartNodes(); // Computes which basic blocks don't have incoming edges in the flow graph.
                                             // Returns this as a set.

    INDEBUG(void fgDispDomTree(DomTreeNode* domTree);) // Helper that prints out the Dominator Tree in debug builds.

    DomTreeNode* fgBuildDomTree(); // Once we compute all the immediate dominator sets for each node in the flow graph
                                   // (performed by fgComputeDoms), this procedure builds the dominance tree represented
                                   // adjacency lists.

    // In order to speed up the queries of the form 'Does A dominates B', we can perform a DFS preorder and postorder
    // traversal of the dominance tree and the dominance query will become A dominates B iif preOrder(A) <= preOrder(B)
    // && postOrder(A) >= postOrder(B) making the computation O(1).
    void fgNumberDomTree(DomTreeNode* domTree);

    // When the flow graph changes, we need to update the block numbers, predecessor lists, reachability sets,
    // dominators, and possibly loops.
    void fgUpdateChangedFlowGraph(const bool computePreds        = true,
                                  const bool computeDoms         = true,
                                  const bool computeReturnBlocks = false,
                                  const bool computeLoops        = false);

public:
    // Compute the predecessors of the blocks in the control flow graph.
    void fgComputePreds();

    // Remove all predecessor information.
    void fgRemovePreds();

    // Compute the cheap flow graph predecessors lists. This is used in some early phases
    // before the full predecessors lists are computed.
    void fgComputeCheapPreds();

private:
    void fgAddCheapPred(BasicBlock* block, BasicBlock* blockPred);

    void fgRemoveCheapPred(BasicBlock* block, BasicBlock* blockPred);

public:
    enum GCPollType
    {
        GCPOLL_NONE,
        GCPOLL_CALL,
        GCPOLL_INLINE
    };

    // Initialize the per-block variable sets (used for liveness analysis).
    void fgInitBlockVarSets();

    PhaseStatus fgInsertGCPolls();
    BasicBlock* fgCreateGCPoll(GCPollType pollType, BasicBlock* block);

    // Requires that "block" is a block that returns from
    // a finally.  Returns the number of successors (jump targets of
    // of blocks in the covered "try" that did a "LEAVE".)
    unsigned fgNSuccsOfFinallyRet(BasicBlock* block);

    // Requires that "block" is a block that returns (in the sense of BBJ_EHFINALLYRET) from
    // a finally.  Returns its "i"th successor (jump targets of
    // of blocks in the covered "try" that did a "LEAVE".)
    // Requires that "i" < fgNSuccsOfFinallyRet(block).
    BasicBlock* fgSuccOfFinallyRet(BasicBlock* block, unsigned i);

private:
    // Factor out common portions of the impls of the methods above.
    void fgSuccOfFinallyRetWork(BasicBlock* block, unsigned i, BasicBlock** bres, unsigned* nres);

public:
    // For many purposes, it is desirable to be able to enumerate the *distinct* targets of a switch statement,
    // skipping duplicate targets.  (E.g., in flow analyses that are only interested in the set of possible targets.)
    // SwitchUniqueSuccSet contains the non-duplicated switch targets.
    // (Code that modifies the jump table of a switch has an obligation to call Compiler::UpdateSwitchTableTarget,
    // which in turn will call the "UpdateTarget" method of this type if a SwitchUniqueSuccSet has already
    // been computed for the switch block.  If a switch block is deleted or is transformed into a non-switch,
    // we leave the entry associated with the block, but it will no longer be accessed.)
    struct SwitchUniqueSuccSet
    {
        unsigned     numDistinctSuccs; // Number of distinct targets of the switch.
        BasicBlock** nonDuplicates;    // Array of "numDistinctSuccs", containing all the distinct switch target
                                       // successors.

        // The switch block "switchBlk" just had an entry with value "from" modified to the value "to".
        // Update "this" as necessary: if "from" is no longer an element of the jump table of "switchBlk",
        // remove it from "this", and ensure that "to" is a member.  Use "alloc" to do any required allocation.
        void UpdateTarget(CompAllocator alloc, BasicBlock* switchBlk, BasicBlock* from, BasicBlock* to);
    };

    typedef JitHashTable<BasicBlock*, JitPtrKeyFuncs<BasicBlock>, SwitchUniqueSuccSet> BlockToSwitchDescMap;

private:
    // Maps BasicBlock*'s that end in switch statements to SwitchUniqueSuccSets that allow
    // iteration over only the distinct successors.
    BlockToSwitchDescMap* m_switchDescMap;

public:
    BlockToSwitchDescMap* GetSwitchDescMap(bool createIfNull = true)
    {
        if ((m_switchDescMap == nullptr) && createIfNull)
        {
            m_switchDescMap = new (getAllocator()) BlockToSwitchDescMap(getAllocator());
        }
        return m_switchDescMap;
    }

    // Invalidate the map of unique switch block successors. For example, since the hash key of the map
    // depends on block numbers, we must invalidate the map when the blocks are renumbered, to ensure that
    // we don't accidentally look up and return the wrong switch data.
    void InvalidateUniqueSwitchSuccMap()
    {
        m_switchDescMap = nullptr;
    }

    // Requires "switchBlock" to be a block that ends in a switch.  Returns
    // the corresponding SwitchUniqueSuccSet.
    SwitchUniqueSuccSet GetDescriptorForSwitch(BasicBlock* switchBlk);

    // The switch block "switchBlk" just had an entry with value "from" modified to the value "to".
    // Update "this" as necessary: if "from" is no longer an element of the jump table of "switchBlk",
    // remove it from "this", and ensure that "to" is a member.
    void UpdateSwitchTableTarget(BasicBlock* switchBlk, BasicBlock* from, BasicBlock* to);

    // Remove the "SwitchUniqueSuccSet" of "switchBlk" in the BlockToSwitchDescMap.
    void fgInvalidateSwitchDescMapEntry(BasicBlock* switchBlk);

    BasicBlock* fgFirstBlockOfHandler(BasicBlock* block);

    bool fgIsFirstBlockOfFilterOrHandler(BasicBlock* block);

    flowList* fgGetPredForBlock(BasicBlock* block, BasicBlock* blockPred);

    flowList* fgGetPredForBlock(BasicBlock* block, BasicBlock* blockPred, flowList*** ptrToPred);

    flowList* fgRemoveRefPred(BasicBlock* block, BasicBlock* blockPred);

    flowList* fgRemoveAllRefPreds(BasicBlock* block, BasicBlock* blockPred);

    void fgRemoveBlockAsPred(BasicBlock* block);

    void fgChangeSwitchBlock(BasicBlock* oldSwitchBlock, BasicBlock* newSwitchBlock);

    void fgReplaceSwitchJumpTarget(BasicBlock* blockSwitch, BasicBlock* newTarget, BasicBlock* oldTarget);

    void fgReplaceJumpTarget(BasicBlock* block, BasicBlock* newTarget, BasicBlock* oldTarget);

    void fgReplacePred(BasicBlock* block, BasicBlock* oldPred, BasicBlock* newPred);

    flowList* fgAddRefPred(BasicBlock* block,
                           BasicBlock* blockPred,
                           flowList*   oldEdge           = nullptr,
                           bool        initializingPreds = false); // Only set to 'true' when we are computing preds in
                                                                   // fgComputePreds()

    void fgFindBasicBlocks();

    bool fgIsBetterFallThrough(BasicBlock* bCur, BasicBlock* bAlt);

    bool fgCheckEHCanInsertAfterBlock(BasicBlock* blk, unsigned regionIndex, bool putInTryRegion);

    BasicBlock* fgFindInsertPoint(unsigned    regionIndex,
                                  bool        putInTryRegion,
                                  BasicBlock* startBlk,
                                  BasicBlock* endBlk,
                                  BasicBlock* nearBlk,
                                  BasicBlock* jumpBlk,
                                  bool        runRarely);

    unsigned fgGetNestingLevel(BasicBlock* block, unsigned* pFinallyNesting = nullptr);

    PhaseStatus fgPostImportationCleanup();

    void fgRemoveStmt(BasicBlock* block, Statement* stmt DEBUGARG(bool isUnlink = false));
    void fgUnlinkStmt(BasicBlock* block, Statement* stmt);

    bool fgCheckRemoveStmt(BasicBlock* block, Statement* stmt);

    bool fgCreateLoopPreHeader(unsigned lnum);

    void fgUnreachableBlock(BasicBlock* block);

    void fgRemoveConditionalJump(BasicBlock* block);

    BasicBlock* fgLastBBInMainFunction();

    BasicBlock* fgEndBBAfterMainFunction();

    BasicBlock* fgGetDomSpeculatively(const BasicBlock* block);

    void fgUnlinkRange(BasicBlock* bBeg, BasicBlock* bEnd);

    void fgRemoveBlock(BasicBlock* block, bool unreachable);

    bool fgCanCompactBlocks(BasicBlock* block, BasicBlock* bNext);

    void fgCompactBlocks(BasicBlock* block, BasicBlock* bNext);

    void fgUpdateLoopsAfterCompacting(BasicBlock* block, BasicBlock* bNext);

    BasicBlock* fgConnectFallThrough(BasicBlock* bSrc, BasicBlock* bDst);

    bool fgRenumberBlocks();

    bool fgExpandRarelyRunBlocks();

    bool fgEhAllowsMoveBlock(BasicBlock* bBefore, BasicBlock* bAfter);

    void fgMoveBlocksAfter(BasicBlock* bStart, BasicBlock* bEnd, BasicBlock* insertAfterBlk);

    PhaseStatus fgTailMerge();

    enum FG_RELOCATE_TYPE
    {
        FG_RELOCATE_TRY,    // relocate the 'try' region
        FG_RELOCATE_HANDLER // relocate the handler region (including the filter if necessary)
    };
    BasicBlock* fgRelocateEHRange(unsigned regionIndex, FG_RELOCATE_TYPE relocateType);

#if defined(FEATURE_EH_FUNCLETS)
#if defined(TARGET_ARM)
    void fgClearFinallyTargetBit(BasicBlock* block);
#endif // defined(TARGET_ARM)
    bool fgIsIntraHandlerPred(BasicBlock* predBlock, BasicBlock* block);
    bool fgAnyIntraHandlerPreds(BasicBlock* block);
    void fgInsertFuncletPrologBlock(BasicBlock* block);
    void        fgCreateFuncletPrologBlocks();
    PhaseStatus fgCreateFunclets();
#else  // !FEATURE_EH_FUNCLETS
    bool fgRelocateEHRegions();
#endif // !FEATURE_EH_FUNCLETS

    bool fgOptimizeUncondBranchToSimpleCond(BasicBlock* block, BasicBlock* target);

    bool fgBlockEndFavorsTailDuplication(BasicBlock* block, unsigned lclNum);

    bool fgBlockIsGoodTailDuplicationCandidate(BasicBlock* block, unsigned* lclNum);

    bool fgOptimizeEmptyBlock(BasicBlock* block);

    bool fgOptimizeBranchToEmptyUnconditional(BasicBlock* block, BasicBlock* bDest);

    bool fgOptimizeBranch(BasicBlock* bJump);

    bool fgOptimizeSwitchBranches(BasicBlock* block);

    bool fgOptimizeBranchToNext(BasicBlock* block, BasicBlock* bNext, BasicBlock* bPrev);

    bool fgOptimizeSwitchJumps();
#ifdef DEBUG
    void fgPrintEdgeWeights();
#endif
    PhaseStatus fgComputeBlockAndEdgeWeights();
    bool fgComputeMissingBlockWeights(weight_t* returnWeight);
    bool fgComputeCalledCount(weight_t returnWeight);
    PhaseStatus fgComputeEdgeWeights();

    bool fgReorderBlocks(bool useProfile);

#ifdef FEATURE_EH_FUNCLETS
    bool fgFuncletsAreCold();
#endif // FEATURE_EH_FUNCLETS

    PhaseStatus fgDetermineFirstColdBlock();

    bool fgIsForwardBranch(BasicBlock* bJump, BasicBlock* bSrc = nullptr);

    bool fgUpdateFlowGraph(bool doTailDup = false, bool isPhase = false);
    PhaseStatus fgUpdateFlowGraphPhase();

    PhaseStatus fgFindOperOrder();

    // method that returns if you should split here
    typedef bool(fgSplitPredicate)(GenTree* tree, GenTree* parent, fgWalkData* data);

    PhaseStatus fgSetBlockOrder();

    void fgRemoveReturnBlock(BasicBlock* block);

    /* Helper code that has been factored out */
    inline void fgConvertBBToThrowBB(BasicBlock* block);

    bool fgCastNeeded(GenTree* tree, var_types toType);
    GenTree* fgDoNormalizeOnStore(GenTree* tree);

    // The following check for loops that don't execute calls
    bool fgLoopCallMarked;

    void fgLoopCallTest(BasicBlock* srcBB, BasicBlock* dstBB);
    void fgLoopCallMark();

    void fgMarkLoopHead(BasicBlock* block);

    unsigned fgGetCodeEstimate(BasicBlock* block);

#if DUMP_FLOWGRAPHS
    enum class PhasePosition
    {
        PrePhase,
        PostPhase
    };
    const char* fgProcessEscapes(const char* nameIn, escapeMapping_t* map);
    static void fgDumpTree(FILE* fgxFile, GenTree* const tree);
    FILE* fgOpenFlowGraphFile(bool* wbDontClose, Phases phase, PhasePosition pos, const char* type);
    bool fgDumpFlowGraph(Phases phase, PhasePosition pos);
#endif // DUMP_FLOWGRAPHS

#ifdef DEBUG

    void fgDispDoms();
    void fgDispReach();
    void fgDispBBLiveness(BasicBlock* block);
    void fgDispBBLiveness();
    void fgTableDispBasicBlock(BasicBlock* block, int ibcColWidth = 0);
    void fgDispBasicBlocks(BasicBlock* firstBlock, BasicBlock* lastBlock, bool dumpTrees);
    void fgDispBasicBlocks(bool dumpTrees = false);
    void fgDumpStmtTree(Statement* stmt, unsigned bbNum);
    void fgDumpBlock(BasicBlock* block);
    void fgDumpTrees(BasicBlock* firstBlock, BasicBlock* lastBlock);

    static fgWalkPreFn fgStress64RsltMulCB;
    void               fgStress64RsltMul();
    void               fgDebugCheckUpdate();

    void fgDebugCheckBBNumIncreasing();
    void fgDebugCheckBBlist(bool checkBBNum = false, bool checkBBRefs = true);
    void fgDebugCheckBlockLinks();
    void fgDebugCheckLinks(bool morphTrees = false);
    void fgDebugCheckStmtsList(BasicBlock* block, bool morphTrees);
    void fgDebugCheckNodeLinks(BasicBlock* block, Statement* stmt);
    void fgDebugCheckNodesUniqueness();
    void fgDebugCheckLoopTable();
    void fgDebugCheckSsa();

    void fgDebugCheckFlags(GenTree* tree);
    void fgDebugCheckDispFlags(GenTree* tree, GenTreeFlags dispFlags, GenTreeDebugFlags debugFlags);
    void fgDebugCheckFlagsHelper(GenTree* tree, GenTreeFlags actualFlags, GenTreeFlags expectedFlags);
    void fgDebugCheckTryFinallyExits();
    void fgDebugCheckProfileWeights();
    bool fgDebugCheckIncomingProfileData(BasicBlock* block);
    bool fgDebugCheckOutgoingProfileData(BasicBlock* block);

#endif // DEBUG

    static bool fgProfileWeightsEqual(weight_t weight1, weight_t weight2);
    static bool fgProfileWeightsConsistent(weight_t weight1, weight_t weight2);

    static GenTree* fgGetFirstNode(GenTree* tree);

    //--------------------- Walking the trees in the IR -----------------------

    struct fgWalkData
    {
        Compiler*     compiler;
        fgWalkPreFn*  wtprVisitorFn;
        fgWalkPostFn* wtpoVisitorFn;
        void*         pCallbackData; // user-provided data
        GenTree*      parent;        // parent of current node, provided to callback
        bool          wtprLclsOnly;  // whether to only visit lclvar nodes
#ifdef DEBUG
        bool printModified; // callback can use this
#endif
    };

    fgWalkResult fgWalkTreePre(GenTree**    pTree,
                               fgWalkPreFn* visitor,
                               void*        pCallBackData = nullptr,
                               bool         lclVarsOnly   = false,
                               bool         computeStack  = false);

    fgWalkResult fgWalkTree(GenTree**     pTree,
                            fgWalkPreFn*  preVisitor,
                            fgWalkPostFn* postVisitor,
                            void*         pCallBackData = nullptr);

    void fgWalkAllTreesPre(fgWalkPreFn* visitor, void* pCallBackData);

    //----- Postorder

    fgWalkResult fgWalkTreePost(GenTree**     pTree,
                                fgWalkPostFn* visitor,
                                void*         pCallBackData = nullptr,
                                bool          computeStack  = false);

    static fgWalkResult fgChkLocAllocCB(GenTree** pTree, Compiler::fgWalkData* data);
    static fgWalkResult fgChkQmarkCB(GenTree** pTree, Compiler::fgWalkData* data);

    /**************************************************************************
     *                          PROTECTED
     *************************************************************************/

protected:
    friend class SsaBuilder;
    friend struct ValueNumberState;

    //--------------------- Detect the basic blocks ---------------------------

    BasicBlock** fgBBs; // Table of pointers to the BBs

    void        fgInitBBLookup();
    BasicBlock* fgLookupBB(unsigned addr);

    bool fgCanSwitchToOptimized();
    void fgSwitchToOptimized(const char* reason);

    bool fgMayExplicitTailCall();

    void fgFindJumpTargets(const BYTE* codeAddr, IL_OFFSET codeSize, FixedBitVect* jumpTarget);

    void fgMarkBackwardJump(BasicBlock* startBlock, BasicBlock* endBlock);

    void fgLinkBasicBlocks();

    unsigned fgMakeBasicBlocks(const BYTE* codeAddr, IL_OFFSET codeSize, FixedBitVect* jumpTarget);

    void fgCheckBasicBlockControlFlow();

    void fgControlFlowPermitted(BasicBlock* blkSrc,
                                BasicBlock* blkDest,
                                bool        IsLeave = false /* is the src a leave block */);

    bool fgFlowToFirstBlockOfInnerTry(BasicBlock* blkSrc, BasicBlock* blkDest, bool sibling);

    void fgObserveInlineConstants(OPCODE opcode, const FgStack& stack, bool isInlining);

    void fgAdjustForAddressExposedOrWrittenThis();

    unsigned fgStressBBProf()
    {
#ifdef DEBUG
        unsigned result = JitConfig.JitStressBBProf();
        if (result == 0)
        {
            if (compStressCompile(STRESS_BB_PROFILE, 15))
            {
                result = 1;
            }
        }
        return result;
#else
        return 0;
#endif
    }

    bool fgHaveProfileData();
    bool fgHaveProfileWeights();
    bool fgGetProfileWeightForBasicBlock(IL_OFFSET offset, weight_t* weight);

    Instrumentor* fgCountInstrumentor;
    Instrumentor* fgHistogramInstrumentor;

    PhaseStatus fgPrepareToInstrumentMethod();
    PhaseStatus fgInstrumentMethod();
    PhaseStatus fgIncorporateProfileData();
    void        fgIncorporateBlockCounts();
    void        fgIncorporateEdgeCounts();

public:
    const char*                            fgPgoFailReason;
    bool                                   fgPgoDisabled;
    ICorJitInfo::PgoSource                 fgPgoSource;
    ICorJitInfo::PgoInstrumentationSchema* fgPgoSchema;
    BYTE*                                  fgPgoData;
    UINT32                                 fgPgoSchemaCount;
    HRESULT                                fgPgoQueryResult;
    UINT32                                 fgNumProfileRuns;
    UINT32                                 fgPgoBlockCounts;
    UINT32                                 fgPgoEdgeCounts;
    UINT32                                 fgPgoClassProfiles;
    UINT32                                 fgPgoMethodProfiles;
    unsigned                               fgPgoInlineePgo;
    unsigned                               fgPgoInlineeNoPgo;
    unsigned                               fgPgoInlineeNoPgoSingleBlock;
    bool                                   fgPgoHaveWeights;

    void WalkSpanningTree(SpanningTreeVisitor* visitor);
    void fgSetProfileWeight(BasicBlock* block, weight_t weight);
    void fgApplyProfileScale();
    bool fgHaveSufficientProfileWeights();
    bool fgHaveTrustedProfileWeights();

    // fgIsUsingProfileWeights - returns true if we have real profile data for this method
    //                           or if we have some fake profile data for the stress mode
    bool fgIsUsingProfileWeights()
    {
        return (fgHaveProfileWeights() || fgStressBBProf());
    }

    // fgProfileRunsCount - returns total number of scenario runs for the profile data
    //                      or BB_UNITY_WEIGHT_UNSIGNED when we aren't using profile data.
    unsigned fgProfileRunsCount()
    {
        return fgIsUsingProfileWeights() ? fgNumProfileRuns : BB_UNITY_WEIGHT_UNSIGNED;
    }

//-------- Insert a statement at the start or end of a basic block --------

#ifdef DEBUG
public:
    static bool fgBlockContainsStatementBounded(BasicBlock* block, Statement* stmt, bool answerOnBoundExceeded = true);
#endif

public:
    Statement* fgNewStmtAtBeg(BasicBlock* block, GenTree* tree, const DebugInfo& di = DebugInfo());
    void fgInsertStmtAtEnd(BasicBlock* block, Statement* stmt);
    Statement* fgNewStmtAtEnd(BasicBlock* block, GenTree* tree, const DebugInfo& di = DebugInfo());
    Statement* fgNewStmtNearEnd(BasicBlock* block, GenTree* tree, const DebugInfo& di = DebugInfo());

private:
    void fgInsertStmtNearEnd(BasicBlock* block, Statement* stmt);
    void fgInsertStmtAtBeg(BasicBlock* block, Statement* stmt);
    void fgInsertStmtAfter(BasicBlock* block, Statement* insertionPoint, Statement* stmt);

public:
    void fgInsertStmtBefore(BasicBlock* block, Statement* insertionPoint, Statement* stmt);

private:
    Statement* fgInsertStmtListAfter(BasicBlock* block, Statement* stmtAfter, Statement* stmtList);

    //                  Create a new temporary variable to hold the result of *ppTree,
    //                  and transform the graph accordingly.
    GenTree* fgInsertCommaFormTemp(GenTree** ppTree, CORINFO_CLASS_HANDLE structType = nullptr);
    TempInfo fgMakeTemp(GenTree* rhs, CORINFO_CLASS_HANDLE structType = nullptr);
    GenTree* fgMakeMultiUse(GenTree** ppTree, CORINFO_CLASS_HANDLE structType = nullptr);

    //                  Recognize a bitwise rotation pattern and convert into a GT_ROL or a GT_ROR node.
    GenTree* fgRecognizeAndMorphBitwiseRotation(GenTree* tree);
    bool fgOperIsBitwiseRotationRoot(genTreeOps oper);

#if !defined(TARGET_64BIT)
    //                  Recognize and morph a long multiplication with 32 bit operands.
    GenTreeOp* fgRecognizeAndMorphLongMul(GenTreeOp* mul);
    GenTreeOp* fgMorphLongMul(GenTreeOp* mul);
#endif

    //-------- Determine the order in which the trees will be evaluated -------
public:
    void fgSetStmtSeq(Statement* stmt);

private:
    GenTree* fgSetTreeSeq(GenTree* tree, bool isLIR = false);
    void fgSetBlockOrder(BasicBlock* block);

    //------------------------- Morphing --------------------------------------

    unsigned fgPtrArgCntMax;

public:
    //------------------------------------------------------------------------
    // fgGetPtrArgCntMax: Return the maximum number of pointer-sized stack arguments that calls inside this method
    // can push on the stack. This value is calculated during morph.
    //
    // Return Value:
    //    Returns fgPtrArgCntMax, that is a private field.
    //
    unsigned fgGetPtrArgCntMax() const
    {
        return fgPtrArgCntMax;
    }

    //------------------------------------------------------------------------
    // fgSetPtrArgCntMax: Set the maximum number of pointer-sized stack arguments that calls inside this method
    // can push on the stack. This function is used during StackLevelSetter to fix incorrect morph calculations.
    //
    void fgSetPtrArgCntMax(unsigned argCntMax)
    {
        fgPtrArgCntMax = argCntMax;
    }

    bool compCanEncodePtrArgCntMax();

private:
    hashBv* fgOutgoingArgTemps;
    hashBv* fgCurrentlyInUseArgTemps;

    void fgSetRngChkTarget(GenTree* tree, bool delay = true);

    BasicBlock* fgSetRngChkTargetInner(SpecialCodeKind kind, bool delay);

#if REARRANGE_ADDS
    void fgMoveOpsLeft(GenTree* tree);
#endif

    bool fgIsCommaThrow(GenTree* tree, bool forFolding = false);

    bool fgIsThrow(GenTree* tree);

    bool fgInDifferentRegions(BasicBlock* blk1, BasicBlock* blk2);
    bool fgIsBlockCold(BasicBlock* block);

    GenTree* fgMorphCastIntoHelper(GenTree* tree, int helper, GenTree* oper);

    GenTree* fgMorphIntoHelperCall(
        GenTree* tree, int helper, bool morphArgs, GenTree* arg1 = nullptr, GenTree* arg2 = nullptr);

    // A "MorphAddrContext" carries information from the surrounding context.  If we are evaluating a byref address,
    // it is useful to know whether the address will be immediately dereferenced, or whether the address value will
    // be used, perhaps by passing it as an argument to a called method.  This affects how null checking is done:
    // for sufficiently small offsets, we can rely on OS page protection to implicitly null-check addresses that we
    // know will be dereferenced.  To know that reliance on implicit null checking is sound, we must further know that
    // all offsets between the top-level indirection and the bottom are constant, and that their sum is sufficiently
    // small; hence the other fields of MorphAddrContext.
    enum MorphAddrContextKind
    {
        MACK_Ind,
        MACK_Addr,
    };
    struct MorphAddrContext
    {
        MorphAddrContextKind m_kind;
        bool                 m_allConstantOffsets; // Valid only for "m_kind == MACK_Ind".  True iff all offsets between
                                                   // top-level indirection and here have been constants.
        size_t m_totalOffset; // Valid only for "m_kind == MACK_Ind", and if "m_allConstantOffsets" is true.
                              // In that case, is the sum of those constant offsets.

        MorphAddrContext(MorphAddrContextKind kind) : m_kind(kind), m_allConstantOffsets(true), m_totalOffset(0)
        {
        }
    };

#ifdef FEATURE_SIMD
    GenTree* getSIMDStructFromField(GenTree*     tree,
                                    CorInfoType* simdBaseJitTypeOut,
                                    unsigned*    indexOut,
                                    unsigned*    simdSizeOut,
                                    bool         ignoreUsedInSIMDIntrinsic = false);
    GenTree* fgMorphFieldAssignToSimdSetElement(GenTree* tree);
    GenTree* fgMorphFieldToSimdGetElement(GenTree* tree);
    bool fgMorphCombineSIMDFieldAssignments(BasicBlock* block, Statement* stmt);
    void impMarkContiguousSIMDFieldAssignments(Statement* stmt);

    // fgPreviousCandidateSIMDFieldAsgStmt is only used for tracking previous simd field assignment
    // in function: Compiler::impMarkContiguousSIMDFieldAssignments.
    Statement* fgPreviousCandidateSIMDFieldAsgStmt;

#endif // FEATURE_SIMD
    GenTree* fgMorphIndexAddr(GenTreeIndexAddr* tree);
    GenTree* fgMorphExpandCast(GenTreeCast* tree);
    GenTreeFieldList* fgMorphLclArgToFieldlist(GenTreeLclVarCommon* lcl);
    GenTreeCall* fgMorphArgs(GenTreeCall* call);

    void fgMakeOutgoingStructArgCopy(GenTreeCall* call, CallArg* arg);

    GenTree* fgMorphLocal(GenTreeLclVarCommon* lclNode);
#ifdef TARGET_X86
    GenTree* fgMorphExpandStackArgForVarArgs(GenTreeLclVarCommon* lclNode);
#endif // TARGET_X86
    GenTree* fgMorphExpandImplicitByRefArg(GenTreeLclVarCommon* lclNode);
    GenTree* fgMorphLocalVar(GenTree* tree, bool forceRemorph);

public:
    bool fgAddrCouldBeNull(GenTree* addr);
    void fgAssignSetVarDef(GenTree* tree);

private:
    GenTree* fgMorphField(GenTree* tree, MorphAddrContext* mac);
    GenTree* fgMorphExpandInstanceField(GenTree* tree, MorphAddrContext* mac);
    GenTree* fgMorphExpandTlsFieldAddr(GenTree* tree);
    bool fgCanFastTailCall(GenTreeCall* call, const char** failReason);
#if FEATURE_FASTTAILCALL
    bool fgCallHasMustCopyByrefParameter(GenTreeCall* callee);
#endif
    bool     fgCheckStmtAfterTailCall();
    GenTree* fgMorphTailCallViaHelpers(GenTreeCall* call, CORINFO_TAILCALL_HELPERS& help);
    bool fgCanTailCallViaJitHelper(GenTreeCall* call);
    void fgMorphTailCallViaJitHelper(GenTreeCall* call);
    GenTree* fgCreateCallDispatcherAndGetResult(GenTreeCall*          origCall,
                                                CORINFO_METHOD_HANDLE callTargetStubHnd,
                                                CORINFO_METHOD_HANDLE dispatcherHnd);
    GenTree* getLookupTree(CORINFO_RESOLVED_TOKEN* pResolvedToken,
                           CORINFO_LOOKUP*         pLookup,
                           GenTreeFlags            handleFlags,
                           void*                   compileTimeHandle);
    GenTree* getRuntimeLookupTree(CORINFO_RESOLVED_TOKEN* pResolvedToken,
                                  CORINFO_LOOKUP*         pLookup,
                                  void*                   compileTimeHandle);
    GenTree* getVirtMethodPointerTree(GenTree*                thisPtr,
                                      CORINFO_RESOLVED_TOKEN* pResolvedToken,
                                      CORINFO_CALL_INFO*      pCallInfo);
    GenTree* getTokenHandleTree(CORINFO_RESOLVED_TOKEN* pResolvedToken, bool parent);

    GenTree* fgMorphPotentialTailCall(GenTreeCall* call);
    void fgValidateIRForTailCall(GenTreeCall* call);
    GenTree* fgGetStubAddrArg(GenTreeCall* call);
    unsigned fgGetArgParameterLclNum(GenTreeCall* call, CallArg* arg);
    void fgMorphRecursiveFastTailCallIntoLoop(BasicBlock* block, GenTreeCall* recursiveTailCall);
    Statement* fgAssignRecursiveCallArgToCallerParam(GenTree*         arg,
                                                     CallArg*         callArg,
                                                     unsigned         lclParamNum,
                                                     BasicBlock*      block,
                                                     const DebugInfo& callDI,
                                                     Statement*       tmpAssignmentInsertionPoint,
                                                     Statement*       paramAssignmentInsertionPoint);
    GenTree* fgMorphCall(GenTreeCall* call);
    GenTree* fgExpandVirtualVtableCallTarget(GenTreeCall* call);

    void fgMorphCallInline(GenTreeCall* call, InlineResult* result);
    void fgMorphCallInlineHelper(GenTreeCall* call, InlineResult* result, InlineContext** createdContext);
#if DEBUG
    void fgNoteNonInlineCandidate(Statement* stmt, GenTreeCall* call);
    static fgWalkPreFn fgFindNonInlineCandidate;
#endif
    GenTree* fgOptimizeDelegateConstructor(GenTreeCall*            call,
                                           CORINFO_CONTEXT_HANDLE* ExactContextHnd,
                                           methodPointerInfo*      ldftnToken);
    GenTree* fgMorphLeaf(GenTree* tree);
    GenTree* fgMorphOneAsgBlockOp(GenTree* tree);
    GenTree* fgMorphInitBlock(GenTree* tree);
    GenTree* fgMorphCopyBlock(GenTree* tree);
    GenTree* fgMorphStoreDynBlock(GenTreeStoreDynBlk* tree);
    GenTree* fgMorphSmpOp(GenTree* tree, MorphAddrContext* mac, bool* optAssertionPropDone = nullptr);
    void fgTryReplaceStructLocalWithField(GenTree* tree);
    GenTree* fgOptimizeCast(GenTreeCast* cast);
    GenTree* fgOptimizeCastOnAssignment(GenTreeOp* asg);
    GenTree* fgOptimizeEqualityComparisonWithConst(GenTreeOp* cmp);
    GenTree* fgOptimizeRelationalComparisonWithConst(GenTreeOp* cmp);
    GenTree* fgOptimizeRelationalComparisonWithFullRangeConst(GenTreeOp* cmp);
#ifdef FEATURE_HW_INTRINSICS
    GenTree* fgOptimizeHWIntrinsic(GenTreeHWIntrinsic* node);
#endif
    GenTree* fgOptimizeCommutativeArithmetic(GenTreeOp* tree);
    GenTree* fgOptimizeRelationalComparisonWithCasts(GenTreeOp* cmp);
    GenTree* fgOptimizeAddition(GenTreeOp* add);
    GenTree* fgOptimizeMultiply(GenTreeOp* mul);
    GenTree* fgOptimizeBitwiseAnd(GenTreeOp* andOp);
    GenTree* fgOptimizeBitwiseXor(GenTreeOp* xorOp);
    GenTree* fgPropagateCommaThrow(GenTree* parent, GenTreeOp* commaThrow, GenTreeFlags precedingSideEffects);
    GenTree* fgMorphRetInd(GenTreeUnOp* tree);
    GenTree* fgMorphModToSubMulDiv(GenTreeOp* tree);
    GenTree* fgMorphUModToAndSub(GenTreeOp* tree);
    GenTree* fgMorphSmpOpOptional(GenTreeOp* tree, bool* optAssertionPropDone);
    GenTree* fgMorphMultiOp(GenTreeMultiOp* multiOp);
    GenTree* fgMorphConst(GenTree* tree);

    GenTreeOp* fgMorphCommutative(GenTreeOp* tree);
    GenTree* fgMorphCastedBitwiseOp(GenTreeOp* tree);

    GenTree* fgMorphReduceAddOps(GenTree* tree);

public:
    GenTree* fgMorphTree(GenTree* tree, MorphAddrContext* mac = nullptr);

private:
    void fgKillDependentAssertionsSingle(unsigned lclNum DEBUGARG(GenTree* tree));
    void fgKillDependentAssertions(unsigned lclNum DEBUGARG(GenTree* tree));
    void fgMorphTreeDone(GenTree* tree);
    void fgMorphTreeDone(GenTree* tree, bool optAssertionPropDone, bool isMorphedTree DEBUGARG(int morphNum = 0));

    Statement* fgMorphStmt;
    unsigned   fgBigOffsetMorphingTemps[TYP_COUNT];

    unsigned fgGetFieldMorphingTemp(GenTreeField* type);

    //----------------------- Liveness analysis -------------------------------

    VARSET_TP fgCurUseSet; // vars used     by block (before an assignment)
    VARSET_TP fgCurDefSet; // vars assigned by block (before a use)

    MemoryKindSet fgCurMemoryUse;   // True iff the current basic block uses memory.
    MemoryKindSet fgCurMemoryDef;   // True iff the current basic block modifies memory.
    MemoryKindSet fgCurMemoryHavoc; // True if  the current basic block is known to set memory to a "havoc" value.

    bool byrefStatesMatchGcHeapStates; // True iff GcHeap and ByrefExposed memory have all the same def points.

    void fgMarkUseDef(GenTreeLclVarCommon* tree);

    void fgBeginScopeLife(VARSET_TP* inScope, VarScopeDsc* var);
    void fgEndScopeLife(VARSET_TP* inScope, VarScopeDsc* var);

    void fgMarkInScope(BasicBlock* block, VARSET_VALARG_TP inScope);
    void fgUnmarkInScope(BasicBlock* block, VARSET_VALARG_TP unmarkScope);

    void fgExtendDbgScopes();
    void fgExtendDbgLifetimes();

#ifdef DEBUG
    void fgDispDebugScopes();
#endif // DEBUG

    //-------------------------------------------------------------------------
    //
    //  The following keeps track of any code we've added for things like array
    //  range checking or explicit calls to enable GC, and so on.
    //
public:
    struct AddCodeDsc
    {
        AddCodeDsc*     acdNext;
        BasicBlock*     acdDstBlk; // block  to  which we jump
        unsigned        acdData;
        SpecialCodeKind acdKind; // what kind of a special block is this?
#if !FEATURE_FIXED_OUT_ARGS
        bool     acdStkLvlInit; // has acdStkLvl value been already set?
        unsigned acdStkLvl;     // stack level in stack slots.
#endif                          // !FEATURE_FIXED_OUT_ARGS
    };

private:
    static unsigned acdHelper(SpecialCodeKind codeKind);

    AddCodeDsc* fgAddCodeList;
    bool        fgAddCodeModf;
    bool        fgRngChkThrowAdded;
    AddCodeDsc* fgExcptnTargetCache[SCK_COUNT];

    BasicBlock* fgRngChkTarget(BasicBlock* block, SpecialCodeKind kind);

    BasicBlock* fgAddCodeRef(BasicBlock* srcBlk, unsigned refData, SpecialCodeKind kind);

public:
    AddCodeDsc* fgFindExcptnTarget(SpecialCodeKind kind, unsigned refData);

    bool fgUseThrowHelperBlocks();

    AddCodeDsc* fgGetAdditionalCodeDescriptors()
    {
        return fgAddCodeList;
    }

private:
    bool fgIsCodeAdded();

    bool fgIsThrowHlpBlk(BasicBlock* block);

#if !FEATURE_FIXED_OUT_ARGS
    unsigned fgThrowHlpBlkStkLevel(BasicBlock* block);
#endif // !FEATURE_FIXED_OUT_ARGS

    unsigned fgCheckInlineDepthAndRecursion(InlineInfo* inlineInfo);
    void fgInvokeInlineeCompiler(GenTreeCall* call, InlineResult* result, InlineContext** createdContext);
    void fgInsertInlineeBlocks(InlineInfo* pInlineInfo);
    Statement* fgInlinePrependStatements(InlineInfo* inlineInfo);
    void fgInlineAppendStatements(InlineInfo* inlineInfo, BasicBlock* block, Statement* stmt);

#ifdef DEBUG
    static fgWalkPreFn fgDebugCheckInlineCandidates;

    void               CheckNoTransformableIndirectCallsRemain();
    static fgWalkPreFn fgDebugCheckForTransformableIndirectCalls;
#endif

    PhaseStatus fgPromoteStructs();
    void fgMorphLocalField(GenTree* tree, GenTree* parent);

    // Reset the refCount for implicit byrefs.
    void fgResetImplicitByRefRefCount();

    // Change implicit byrefs' types from struct to pointer, and for any that were
    // promoted, create new promoted struct temps.
    PhaseStatus fgRetypeImplicitByRefArgs();

    // Clear up annotations for any struct promotion temps created for implicit byrefs.
    void fgMarkDemotedImplicitByRefArgs();

    PhaseStatus fgMarkAddressExposedLocals();
    void fgMarkAddressExposedLocals(Statement* stmt);

    PhaseStatus fgForwardSub();
    bool fgForwardSubBlock(BasicBlock* block);
    bool fgForwardSubStatement(Statement* statement);

    // The given local variable, required to be a struct variable, is being assigned via
    // a "lclField", to make it masquerade as an integral type in the ABI.  Make sure that
    // the variable is not enregistered, and is therefore not promoted independently.
    void fgLclFldAssign(unsigned lclNum);

    enum TypeProducerKind
    {
        TPK_Unknown = 0, // May not be a RuntimeType
        TPK_Handle  = 1, // RuntimeType via handle
        TPK_GetType = 2, // RuntimeType via Object.get_Type()
        TPK_Null    = 3, // Tree value is null
        TPK_Other   = 4  // RuntimeType via other means
    };

    TypeProducerKind gtGetTypeProducerKind(GenTree* tree);
    bool gtIsTypeHandleToRuntimeTypeHelper(GenTreeCall* call);
    bool gtIsTypeHandleToRuntimeTypeHandleHelper(GenTreeCall* call, CorInfoHelpFunc* pHelper = nullptr);
    bool gtIsActiveCSE_Candidate(GenTree* tree);

    ExceptionSetFlags gtCollectExceptions(GenTree* tree);

    bool fgIsBigOffset(size_t offset);

    bool fgNeedReturnSpillTemp();

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX                           Optimizer                                       XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */

public:
    void optInit();

    PhaseStatus rangeCheckPhase();
    GenTree* optRemoveRangeCheck(GenTreeBoundsChk* check, GenTree* comma, Statement* stmt);
    GenTree* optRemoveStandaloneRangeCheck(GenTreeBoundsChk* check, Statement* stmt);
    void optRemoveCommaBasedRangeCheck(GenTree* comma, Statement* stmt);

protected:
    // Do hoisting for all loops.
    PhaseStatus optHoistLoopCode();

    // To represent sets of VN's that have already been hoisted in outer loops.
    typedef JitHashTable<ValueNum, JitSmallPrimitiveKeyFuncs<ValueNum>, bool> VNSet;

    struct LoopHoistContext
    {
    private:
        // The set of variables hoisted in the current loop (or nullptr if there are none).
        VNSet* m_pHoistedInCurLoop;

    public:
        // Value numbers of expressions that have been hoisted in the current (or most recent) loop in the nest.
        // Previous decisions on loop-invariance of value numbers in the current loop.
        VNSet m_curLoopVnInvariantCache;

        // Get the VN cache for current loop
        VNSet* GetHoistedInCurLoop(Compiler* comp)
        {
            if (m_pHoistedInCurLoop == nullptr)
            {
                m_pHoistedInCurLoop = new (comp->getAllocatorLoopHoist()) VNSet(comp->getAllocatorLoopHoist());
            }
            return m_pHoistedInCurLoop;
        }

        // Return the so far collected VNs in cache for current loop and reset it.
        void ResetHoistedInCurLoop()
        {
            m_pHoistedInCurLoop = nullptr;
            JITDUMP("Resetting m_pHoistedInCurLoop\n");
        }

        LoopHoistContext(Compiler* comp)
            : m_pHoistedInCurLoop(nullptr), m_curLoopVnInvariantCache(comp->getAllocatorLoopHoist())
        {
        }
    };

    // Do hoisting of all loops nested within loop "lnum" (an index into the optLoopTable), followed
    // by the loop "lnum" itself.
    bool optHoistLoopNest(unsigned lnum, LoopHoistContext* hoistCtxt);

    // Do hoisting for a particular loop ("lnum" is an index into the optLoopTable.)
    bool optHoistThisLoop(unsigned lnum, LoopHoistContext* hoistCtxt, BasicBlockList* existingPreHeaders);

    // Hoist all expressions in "blocks" that are invariant in loop "loopNum" (an index into the optLoopTable)
    // outside of that loop.
    void optHoistLoopBlocks(unsigned loopNum, ArrayStack<BasicBlock*>* blocks, LoopHoistContext* hoistContext);

    // Return true if the tree looks profitable to hoist out of loop 'lnum'.
    bool optIsProfitableToHoistTree(GenTree* tree, unsigned lnum);

    // Performs the hoisting 'tree' into the PreHeader for loop 'lnum'
    void optHoistCandidate(GenTree* tree, BasicBlock* treeBb, unsigned lnum, LoopHoistContext* hoistCtxt);

    // Note the new SSA uses in tree
    void optRecordSsaUses(GenTree* tree, BasicBlock* block);

    // Returns true iff the ValueNum "vn" represents a value that is loop-invariant in "lnum".
    //   Constants and init values are always loop invariant.
    //   VNPhi's connect VN's to the SSA definition, so we can know if the SSA def occurs in the loop.
    bool optVNIsLoopInvariant(ValueNum vn, unsigned lnum, VNSet* recordedVNs);

    // If "blk" is the entry block of a natural loop, returns true and sets "*pLnum" to the index of the loop
    // in the loop table.
    bool optBlockIsLoopEntry(BasicBlock* blk, unsigned* pLnum);

    // Records the set of "side effects" of all loops: fields (object instance and static)
    // written to, and SZ-array element type equivalence classes updated.
    void optComputeLoopSideEffects();

#ifdef DEBUG
    bool optAnyChildNotRemoved(unsigned loopNum);
#endif // DEBUG

    // Mark a loop as removed.
    void optMarkLoopRemoved(unsigned loopNum);

    // During global assertion prop, returns the conservative normal VN for a tree;
    // otherwise returns NoVN
    ValueNum optConservativeNormalVN(GenTree* tree);

private:
    // Requires "lnum" to be the index of an outermost loop in the loop table.  Traverses the body of that loop,
    // including all nested loops, and records the set of "side effects" of the loop: fields (object instance and
    // static) written to, and SZ-array element type equivalence classes updated.
    void optComputeLoopNestSideEffects(unsigned lnum);

    // Given a loop number 'lnum' mark it and any nested loops as having 'memoryHavoc'
    void optRecordLoopNestsMemoryHavoc(unsigned lnum, MemoryKindSet memoryHavoc);

    // Add the side effects of "blk" (which is required to be within a loop) to all loops of which it is a part.
    // Returns false if we encounter a block that is not marked as being inside a loop.
    //
    bool optComputeLoopSideEffectsOfBlock(BasicBlock* blk);

    // Hoist the expression "expr" out of loop "lnum".
    void optPerformHoistExpr(GenTree* expr, BasicBlock* exprBb, unsigned lnum);

public:
    PhaseStatus optOptimizeBools();

public:
    PhaseStatus optInvertLoops();    // Invert loops so they're entered at top and tested at bottom.
    PhaseStatus optOptimizeFlow();   // Simplify flow graph and do tail duplication
    PhaseStatus optOptimizeLayout(); // Optimize the BasicBlock layout of the method
    PhaseStatus optSetBlockWeights();
    PhaseStatus optFindLoopsPhase(); // Finds loops and records them in the loop table

    void optFindLoops();

    PhaseStatus optCloneLoops();
    void optCloneLoop(unsigned loopInd, LoopCloneContext* context);
    void optEnsureUniqueHead(unsigned loopInd, weight_t ambientWeight);
    PhaseStatus optUnrollLoops(); // Unrolls loops (needs to have cost info)
    void        optRemoveRedundantZeroInits();
    PhaseStatus optIfConversion(); // If conversion

protected:
    // This enumeration describes what is killed by a call.

    enum callInterf
    {
        CALLINT_NONE,       // no interference                               (most helpers)
        CALLINT_REF_INDIRS, // kills GC ref indirections                     (SETFIELD OBJ)
        CALLINT_SCL_INDIRS, // kills non GC ref indirections                 (SETFIELD non-OBJ)
        CALLINT_ALL_INDIRS, // kills both GC ref and non GC ref indirections (SETFIELD STRUCT)
        CALLINT_ALL,        // kills everything                              (normal method call)
    };

    enum class FieldKindForVN
    {
        SimpleStatic,
        WithBaseAddr
    };

public:
    // A "LoopDsc" describes a ("natural") loop.  We (currently) require the body of a loop to be a contiguous (in
    // bbNext order) sequence of basic blocks.  (At times, we may require the blocks in a loop to be "properly numbered"
    // in bbNext order; we use comparisons on the bbNum to decide order.)
    // The blocks that define the body are
    //   top <= entry <= bottom
    // The "head" of the loop is a block outside the loop that has "entry" as a successor. We only support loops with a
    // single 'head' block. The meanings of these blocks are given in the definitions below. Also see the picture at
    // Compiler::optFindNaturalLoops().
    struct LoopDsc
    {
        BasicBlock* lpHead;   // HEAD of the loop (not part of the looping of the loop) -- has ENTRY as a successor.
        BasicBlock* lpTop;    // loop TOP (the back edge from lpBottom reaches here). Lexically first block (in bbNext
                              // order) reachable in this loop.
        BasicBlock* lpEntry;  // the ENTRY in the loop (in most cases TOP or BOTTOM)
        BasicBlock* lpBottom; // loop BOTTOM (from here we have a back edge to the TOP)
        BasicBlock* lpExit;   // if a single exit loop this is the EXIT (in most cases BOTTOM)

        callInterf   lpAsgCall;     // "callInterf" for calls in the loop
        ALLVARSET_TP lpAsgVars;     // set of vars assigned within the loop (all vars, not just tracked)
        varRefKinds  lpAsgInds : 8; // set of inds modified within the loop

        LoopFlags lpFlags;

        unsigned char lpExitCnt; // number of exits from the loop

        unsigned char lpParent;  // The index of the most-nested loop that completely contains this one,
                                 // or else BasicBlock::NOT_IN_LOOP if no such loop exists.
        unsigned char lpChild;   // The index of a nested loop, or else BasicBlock::NOT_IN_LOOP if no child exists.
                                 // (Actually, an "immediately" nested loop --
                                 // no other child of this loop is a parent of lpChild.)
        unsigned char lpSibling; // The index of another loop that is an immediate child of lpParent,
                                 // or else BasicBlock::NOT_IN_LOOP.  One can enumerate all the children of a loop
                                 // by following "lpChild" then "lpSibling" links.

        bool lpLoopHasMemoryHavoc[MemoryKindCount]; // The loop contains an operation that we assume has arbitrary
                                                    // memory side effects.  If this is set, the fields below
                                                    // may not be accurate (since they become irrelevant.)

        VARSET_TP lpVarInOut;  // The set of variables that are IN or OUT during the execution of this loop
        VARSET_TP lpVarUseDef; // The set of variables that are USE or DEF during the execution of this loop

        // The following counts are used for hoisting profitability checks.

        int lpHoistedExprCount; // The register count for the non-FP expressions from inside this loop that have been
                                // hoisted
        int lpLoopVarCount;     // The register count for the non-FP LclVars that are read/written inside this loop
        int lpVarInOutCount;    // The register count for the non-FP LclVars that are alive inside or across this loop

        int lpHoistedFPExprCount; // The register count for the FP expressions from inside this loop that have been
                                  // hoisted
        int lpLoopVarFPCount;     // The register count for the FP LclVars that are read/written inside this loop
        int lpVarInOutFPCount;    // The register count for the FP LclVars that are alive inside or across this loop

        bool lpHoistAddedPreheader; // The loop preheader was added during hoisting

        typedef JitHashTable<CORINFO_FIELD_HANDLE, JitPtrKeyFuncs<struct CORINFO_FIELD_STRUCT_>, FieldKindForVN>
                        FieldHandleSet;
        FieldHandleSet* lpFieldsModified; // This has entries for all static field and object instance fields modified
                                          // in the loop.

        typedef JitHashTable<CORINFO_CLASS_HANDLE, JitPtrKeyFuncs<struct CORINFO_CLASS_STRUCT_>, bool> ClassHandleSet;
        ClassHandleSet* lpArrayElemTypesModified; // Bits set indicate the set of sz array element types such that
                                                  // arrays of that type are modified
                                                  // in the loop.

        // Adds the variable liveness information for 'blk' to 'this' LoopDsc
        void AddVariableLiveness(Compiler* comp, BasicBlock* blk);

        inline void AddModifiedField(Compiler* comp, CORINFO_FIELD_HANDLE fldHnd, FieldKindForVN fieldKind);
        // This doesn't *always* take a class handle -- it can also take primitive types, encoded as class handles
        // (shifted left, with a low-order bit set to distinguish.)
        // Use the {Encode/Decode}ElemType methods to construct/destruct these.
        inline void AddModifiedElemType(Compiler* comp, CORINFO_CLASS_HANDLE structHnd);

        /* The following values are set only for iterator loops, i.e. has the flag LPFLG_ITER set */

        GenTree*   lpIterTree;          // The "i = i <op> const" tree
        unsigned   lpIterVar() const;   // iterator variable #
        int        lpIterConst() const; // the constant with which the iterator is incremented
        genTreeOps lpIterOper() const;  // the type of the operation on the iterator (ASG_ADD, ASG_SUB, etc.)
        void       VERIFY_lpIterTree() const;

        var_types lpIterOperType() const; // For overflow instructions

        // Set to the block where we found the initialization for LPFLG_CONST_INIT loops.
        // Initially, this will be 'head', but 'head' might change if we insert a loop pre-header block.
        BasicBlock* lpInitBlock;

        int lpConstInit; // initial constant value of iterator : Valid if LPFLG_CONST_INIT

        // The following is for LPFLG_ITER loops only (i.e. the loop condition is "i RELOP const or var")

        GenTree*   lpTestTree;         // pointer to the node containing the loop test
        genTreeOps lpTestOper() const; // the type of the comparison between the iterator and the limit (GT_LE, GT_GE,
                                       // etc.)

        bool lpIsIncreasingLoop() const; // if the loop iterator increases from low to high value.
        bool lpIsDecreasingLoop() const; // if the loop iterator decreases from high to low value.

        void VERIFY_lpTestTree() const;

        bool     lpIsReversed() const; // true if the iterator node is the second operand in the loop condition
        GenTree* lpIterator() const;   // the iterator node in the loop test
        GenTree* lpLimit() const;      // the limit node in the loop test

        // Limit constant value of iterator - loop condition is "i RELOP const"
        // : Valid if LPFLG_CONST_LIMIT
        int lpConstLimit() const;

        // The lclVar # in the loop condition ( "i RELOP lclVar" )
        // : Valid if LPFLG_VAR_LIMIT
        unsigned lpVarLimit() const;

        // The array length in the loop condition ( "i RELOP arr.len" or "i RELOP arr[i][j].len" )
        // : Valid if LPFLG_ARRLEN_LIMIT
        bool lpArrLenLimit(Compiler* comp, ArrIndex* index) const;

        // Returns "true" iff this is a "top entry" loop.
        bool lpIsTopEntry() const
        {
            if (lpHead->bbNext == lpEntry)
            {
                assert(lpHead->bbFallsThrough());
                assert(lpTop == lpEntry);
                return true;
            }
            else
            {
                return false;
            }
        }

        // Returns "true" iff this is removed loop.
        bool lpIsRemoved() const
        {
            return (lpFlags & LPFLG_REMOVED) != 0;
        }

        // Returns "true" iff "*this" contains the blk.
        bool lpContains(BasicBlock* blk) const
        {
            return lpTop->bbNum <= blk->bbNum && blk->bbNum <= lpBottom->bbNum;
        }

        // Returns "true" iff "*this" (properly) contains the range [top, bottom] (allowing tops
        // to be equal, but requiring bottoms to be different.)
        bool lpContains(BasicBlock* top, BasicBlock* bottom) const
        {
            return lpTop->bbNum <= top->bbNum && bottom->bbNum < lpBottom->bbNum;
        }

        // Returns "true" iff "*this" (properly) contains "lp2" (allowing tops to be equal, but requiring
        // bottoms to be different.)
        bool lpContains(const LoopDsc& lp2) const
        {
            return lpContains(lp2.lpTop, lp2.lpBottom);
        }

        // Returns "true" iff "*this" is (properly) contained by the range [top, bottom]
        // (allowing tops to be equal, but requiring bottoms to be different.)
        bool lpContainedBy(BasicBlock* top, BasicBlock* bottom) const
        {
            return top->bbNum <= lpTop->bbNum && lpBottom->bbNum < bottom->bbNum;
        }

        // Returns "true" iff "*this" is (properly) contained by "lp2"
        // (allowing tops to be equal, but requiring bottoms to be different.)
        bool lpContainedBy(const LoopDsc& lp2) const
        {
            return lpContainedBy(lp2.lpTop, lp2.lpBottom);
        }

        // Returns "true" iff "*this" is disjoint from the range [top, bottom].
        bool lpDisjoint(BasicBlock* top, BasicBlock* bottom) const
        {
            return bottom->bbNum < lpTop->bbNum || lpBottom->bbNum < top->bbNum;
        }
        // Returns "true" iff "*this" is disjoint from "lp2".
        bool lpDisjoint(const LoopDsc& lp2) const
        {
            return lpDisjoint(lp2.lpTop, lp2.lpBottom);
        }

        // Returns "true" iff the loop is well-formed (see code for defn).
        bool lpWellFormed() const
        {
            return lpTop->bbNum <= lpEntry->bbNum && lpEntry->bbNum <= lpBottom->bbNum &&
                   (lpHead->bbNum < lpTop->bbNum || lpHead->bbNum > lpBottom->bbNum);
        }

#ifdef DEBUG
        void lpValidatePreHeader() const
        {
            // If this is called, we expect there to be a pre-header.
            assert(lpFlags & LPFLG_HAS_PREHEAD);

            // The pre-header must unconditionally enter the loop.
            assert(lpHead->GetUniqueSucc() == lpEntry);

            // The loop block must be marked as a pre-header.
            assert(lpHead->bbFlags & BBF_LOOP_PREHEADER);

            // The loop entry must have a single non-loop predecessor, which is the pre-header.
            // We can't assume here that the bbNum are properly ordered, so we can't do a simple lpContained()
            // check. So, we defer this check, which will be done by `fgDebugCheckLoopTable()`.
        }
#endif // DEBUG

        // LoopBlocks: convenience method for enabling range-based `for` iteration over all the
        // blocks in a loop, e.g.:
        //    for (BasicBlock* const block : loop->LoopBlocks()) ...
        // Currently, the loop blocks are expected to be in linear, lexical, `bbNext` order
        // from `lpTop` through `lpBottom`, inclusive. All blocks in this range are considered
        // to be part of the loop.
        //
        BasicBlockRangeList LoopBlocks() const
        {
            return BasicBlockRangeList(lpTop, lpBottom);
        }
    };

protected:
    bool fgMightHaveLoop(); // returns true if there are any back edges
    bool fgHasLoops;        // True if this method has any loops, set in fgComputeReachability

public:
    LoopDsc*      optLoopTable;        // loop descriptor table
    bool          optLoopTableValid;   // info in loop table should be valid
    unsigned char optLoopCount;        // number of tracked loops
    unsigned char loopAlignCandidates; // number of loops identified for alignment

    // Every time we rebuild the loop table, we increase the global "loop epoch". Any loop indices or
    // loop table pointers from the previous epoch are invalid.
    // TODO: validate this in some way?
    unsigned optCurLoopEpoch;

    void NewLoopEpoch()
    {
        ++optCurLoopEpoch;
        JITDUMP("New loop epoch %d\n", optCurLoopEpoch);
    }

#ifdef DEBUG
    unsigned char loopsAligned; // number of loops actually aligned
#endif                          // DEBUG

    bool optRecordLoop(BasicBlock*   head,
                       BasicBlock*   top,
                       BasicBlock*   entry,
                       BasicBlock*   bottom,
                       BasicBlock*   exit,
                       unsigned char exitCnt);

    PhaseStatus optClearLoopIterInfo();

#ifdef DEBUG
    void optPrintLoopInfo(unsigned lnum, bool printVerbose = false);
    void optPrintLoopInfo(const LoopDsc* loop, bool printVerbose = false);
    void optPrintLoopTable();
#endif

protected:
    unsigned optCallCount;         // number of calls made in the method
    unsigned optIndirectCallCount; // number of virtual, interface and indirect calls made in the method
    unsigned optNativeCallCount;   // number of Pinvoke/Native calls made in the method
    unsigned optLoopsCloned;       // number of loops cloned in the current method.

#ifdef DEBUG
    void optCheckPreds();
#endif

    void optResetLoopInfo();
    void optFindAndScaleGeneralLoopBlocks();

    // Determine if there are any potential loops, and set BBF_LOOP_HEAD on potential loop heads.
    void optMarkLoopHeads();

    void optScaleLoopBlocks(BasicBlock* begBlk, BasicBlock* endBlk);

    void optUnmarkLoopBlocks(BasicBlock* begBlk, BasicBlock* endBlk);

    void optUpdateLoopsBeforeRemoveBlock(BasicBlock* block, bool skipUnmarkLoop = false);

    bool optIsLoopTestEvalIntoTemp(Statement* testStmt, Statement** newTestStmt);
    unsigned optIsLoopIncrTree(GenTree* incr);
    bool optCheckIterInLoopTest(unsigned loopInd, GenTree* test, unsigned iterVar);
    bool optComputeIterInfo(GenTree* incr, BasicBlock* from, BasicBlock* to, unsigned* pIterVar);
    bool optPopulateInitInfo(unsigned loopInd, BasicBlock* initBlock, GenTree* init, unsigned iterVar);
    bool optExtractInitTestIncr(
        BasicBlock* head, BasicBlock* bottom, BasicBlock* exit, GenTree** ppInit, GenTree** ppTest, GenTree** ppIncr);

    void optFindNaturalLoops();

    void optIdentifyLoopsForAlignment();

    // Ensures that all the loops in the loop nest rooted at "loopInd" (an index into the loop table) are 'canonical' --
    // each loop has a unique "top."  Returns "true" iff the flowgraph has been modified.
    bool optCanonicalizeLoopNest(unsigned char loopInd);

    // Ensures that the loop "loopInd" (an index into the loop table) is 'canonical' -- it has a unique "top,"
    // unshared with any other loop.  Returns "true" iff the flowgraph has been modified
    bool optCanonicalizeLoop(unsigned char loopInd);

    enum class LoopCanonicalizationOption
    {
        Outer,
        Current
    };

    bool optCanonicalizeLoopCore(unsigned char loopInd, LoopCanonicalizationOption option);

    // Requires "l1" to be a valid loop table index, and not "BasicBlock::NOT_IN_LOOP".
    // Requires "l2" to be a valid loop table index, or else "BasicBlock::NOT_IN_LOOP".
    // Returns true iff "l2" is not NOT_IN_LOOP, and "l1" contains "l2".
    // A loop contains itself.
    bool optLoopContains(unsigned l1, unsigned l2) const;

    // Returns the lpEntry for given preheader block of a loop
    BasicBlock* optLoopEntry(BasicBlock* preHeader);

    // Updates the loop table by changing loop "loopInd", whose head is required
    // to be "from", to be "to".  Also performs this transformation for any
    // loop nested in "loopInd" that shares the same head as "loopInd".
    void optUpdateLoopHead(unsigned loopInd, BasicBlock* from, BasicBlock* to);

    void optRedirectBlock(BasicBlock* blk, BlockToBlockMap* redirectMap, const bool updatePreds = false);

    // Marks the containsCall information to "lnum" and any parent loops.
    void AddContainsCallAllContainingLoops(unsigned lnum);

    // Adds the variable liveness information from 'blk' to "lnum" and any parent loops.
    void AddVariableLivenessAllContainingLoops(unsigned lnum, BasicBlock* blk);

    // Adds "fldHnd" to the set of modified fields of "lnum" and any parent loops.
    void AddModifiedFieldAllContainingLoops(unsigned lnum, CORINFO_FIELD_HANDLE fldHnd, FieldKindForVN fieldKind);

    // Adds "elemType" to the set of modified array element types of "lnum" and any parent loops.
    void AddModifiedElemTypeAllContainingLoops(unsigned lnum, CORINFO_CLASS_HANDLE elemType);

    // Requires that "from" and "to" have the same "bbJumpKind" (perhaps because "to" is a clone
    // of "from".)  Copies the jump destination from "from" to "to".
    void optCopyBlkDest(BasicBlock* from, BasicBlock* to);

    // Returns true if 'block' is an entry block for any loop in 'optLoopTable'
    bool optIsLoopEntry(BasicBlock* block) const;

    // The depth of the loop described by "lnum" (an index into the loop table.) (0 == top level)
    unsigned optLoopDepth(unsigned lnum)
    {
        assert(lnum < optLoopCount);
        unsigned depth = 0;
        while ((lnum = optLoopTable[lnum].lpParent) != BasicBlock::NOT_IN_LOOP)
        {
            ++depth;
        }
        return depth;
    }

    // Struct used in optInvertWhileLoop to count interesting constructs to boost the profitability score.
    struct OptInvertCountTreeInfoType
    {
        int sharedStaticHelperCount;
        int arrayLengthCount;
    };

    OptInvertCountTreeInfoType optInvertCountTreeInfo(GenTree* tree);

    bool optInvertWhileLoop(BasicBlock* block);
    bool optIfConvert(BasicBlock* block);

private:
    static bool optIterSmallOverflow(int iterAtExit, var_types incrType);
    static bool optIterSmallUnderflow(int iterAtExit, var_types decrType);

    bool optComputeLoopRep(int        constInit,
                           int        constLimit,
                           int        iterInc,
                           genTreeOps iterOper,
                           var_types  iterType,
                           genTreeOps testOper,
                           bool       unsignedTest,
                           bool       dupCond,
                           unsigned*  iterCount);

protected:
    struct isVarAssgDsc
    {
        GenTree*     ivaSkip;
        ALLVARSET_TP ivaMaskVal;        // Set of variables assigned to.  This is a set of all vars, not tracked vars.
        unsigned     ivaVar;            // Variable we are interested in, or -1
        varRefKinds  ivaMaskInd;        // What kind of indirect assignments are there?
        callInterf   ivaMaskCall;       // What kind of calls are there?
        bool         ivaMaskIncomplete; // Variables not representable in ivaMaskVal were assigned to.
    };

    bool optIsVarAssignedWithDesc(Statement* stmt, isVarAssgDsc* dsc);

    bool optIsVarAssigned(BasicBlock* beg, BasicBlock* end, GenTree* skip, unsigned var);

    bool optIsVarAssgLoop(unsigned lnum, unsigned var);

    bool optIsSetAssgLoop(unsigned lnum, ALLVARSET_VALARG_TP vars, varRefKinds inds = VR_NONE);

    bool optNarrowTree(GenTree* tree, var_types srct, var_types dstt, ValueNumPair vnpNarrow, bool doit);

protected:
    //  The following is the upper limit on how many expressions we'll keep track
    //  of for the CSE analysis.
    //
    static const unsigned MAX_CSE_CNT = EXPSET_SZ;

    static const int MIN_CSE_COST = 2;

    // BitVec trait information only used by the optCSE_canSwap() method, for the  CSE_defMask and CSE_useMask.
    // This BitVec uses one bit per CSE candidate
    BitVecTraits* cseMaskTraits; // one bit per CSE candidate

    // BitVec trait information for computing CSE availability using the CSE_DataFlow algorithm.
    // Two bits are allocated per CSE candidate to compute CSE availability
    // plus an extra bit to handle the initial unvisited case.
    // (See CSE_DataFlow::EndMerge for an explanation of why this is necessary.)
    //
    // The two bits per CSE candidate have the following meanings:
    //     11 - The CSE is available, and is also available when considering calls as killing availability.
    //     10 - The CSE is available, but is not available when considering calls as killing availability.
    //     00 - The CSE is not available
    //     01 - An illegal combination
    //
    BitVecTraits* cseLivenessTraits;

    //-----------------------------------------------------------------------------------------------------------------
    // getCSEnum2bit: Return the normalized index to use in the EXPSET_TP for the CSE with the given CSE index.
    // Each GenTree has a `gtCSEnum` field. Zero is reserved to mean this node is not a CSE, positive values indicate
    // CSE uses, and negative values indicate CSE defs. The caller must pass a non-zero positive value, as from
    // GET_CSE_INDEX().
    //
    static unsigned genCSEnum2bit(unsigned CSEnum)
    {
        assert((CSEnum > 0) && (CSEnum <= MAX_CSE_CNT));
        return CSEnum - 1;
    }

    //-----------------------------------------------------------------------------------------------------------------
    // getCSEAvailBit: Return the bit used by CSE dataflow sets (bbCseGen, etc.) for the availability bit for a CSE.
    //
    static unsigned getCSEAvailBit(unsigned CSEnum)
    {
        return genCSEnum2bit(CSEnum) * 2;
    }

    //-----------------------------------------------------------------------------------------------------------------
    // getCSEAvailCrossCallBit: Return the bit used by CSE dataflow sets (bbCseGen, etc.) for the availability bit
    // for a CSE considering calls as killing availability bit (see description above).
    //
    static unsigned getCSEAvailCrossCallBit(unsigned CSEnum)
    {
        return getCSEAvailBit(CSEnum) + 1;
    }

    void optPrintCSEDataFlowSet(EXPSET_VALARG_TP cseDataFlowSet, bool includeBits = true);

    EXPSET_TP cseCallKillsMask; // Computed once - A mask that is used to kill available CSEs at callsites

    /* Generic list of nodes - used by the CSE logic */

    struct treeLst
    {
        treeLst* tlNext;
        GenTree* tlTree;
    };

    struct treeStmtLst
    {
        treeStmtLst* tslNext;
        GenTree*     tslTree;  // tree node
        Statement*   tslStmt;  // statement containing the tree
        BasicBlock*  tslBlock; // block containing the statement
    };

    // The following logic keeps track of expressions via a simple hash table.

    struct CSEdsc
    {
        CSEdsc*  csdNextInBucket;  // used by the hash table
        size_t   csdHashKey;       // the original hashkey
        ssize_t  csdConstDefValue; // When we CSE similar constants, this is the value that we use as the def
        ValueNum csdConstDefVN;    // When we CSE similar constants, this is the ValueNumber that we use for the LclVar
                                   // assignment
        unsigned csdIndex;         // 1..optCSECandidateCount
        bool     csdIsSharedConst; // true if this CSE is a shared const
        bool     csdLiveAcrossCall;

        unsigned short csdDefCount; // definition   count
        unsigned short csdUseCount; // use          count  (excluding the implicit uses at defs)

        weight_t csdDefWtCnt; // weighted def count
        weight_t csdUseWtCnt; // weighted use count  (excluding the implicit uses at defs)

        GenTree*    csdTree;  // treenode containing the 1st occurrence
        Statement*  csdStmt;  // stmt containing the 1st occurrence
        BasicBlock* csdBlock; // block containing the 1st occurrence

        treeStmtLst* csdTreeList; // list of matching tree nodes: head
        treeStmtLst* csdTreeLast; // list of matching tree nodes: tail

        // ToDo: This can be removed when gtGetStructHandleIfPresent stops guessing
        // and GT_IND nodes always have valid struct handle.
        //
        CORINFO_CLASS_HANDLE csdStructHnd; // The class handle, currently needed to create a SIMD LclVar in PerformCSE
        bool                 csdStructHndMismatch;

        ValueNum defExcSetPromise; // The exception set that is now required for all defs of this CSE.
                                   // This will be set to NoVN if we decide to abandon this CSE

        ValueNum defExcSetCurrent; // The set of exceptions we currently can use for CSE uses.

        ValueNum defConservNormVN; // if all def occurrences share the same conservative normal value
                                   // number, this will reflect it; otherwise, NoVN.
                                   // not used for shared const CSE's
    };

    static const size_t s_optCSEhashSizeInitial;
    static const size_t s_optCSEhashGrowthFactor;
    static const size_t s_optCSEhashBucketSize;
    size_t              optCSEhashSize;                 // The current size of hashtable
    size_t              optCSEhashCount;                // Number of entries in hashtable
    size_t              optCSEhashMaxCountBeforeResize; // Number of entries before resize
    CSEdsc**            optCSEhash;
    CSEdsc**            optCSEtab;

    typedef JitHashTable<GenTree*, JitPtrKeyFuncs<GenTree>, GenTree*> NodeToNodeMap;

    NodeToNodeMap* optCseCheckedBoundMap; // Maps bound nodes to ancestor compares that should be
                                          // re-numbered with the bound to improve range check elimination

    // Given a compare, look for a cse candidate checked bound feeding it and add a map entry if found.
    void optCseUpdateCheckedBoundMap(GenTree* compare);

    void optCSEstop();

    CSEdsc* optCSEfindDsc(unsigned index);
    bool optUnmarkCSE(GenTree* tree);

    // user defined callback data for the tree walk function optCSE_MaskHelper()
    struct optCSE_MaskData
    {
        EXPSET_TP CSE_defMask;
        EXPSET_TP CSE_useMask;
    };

    // Treewalk helper for optCSE_DefMask and optCSE_UseMask
    static fgWalkPreFn optCSE_MaskHelper;

    // This function walks all the node for an given tree
    // and return the mask of CSE definitions and uses for the tree
    //
    void optCSE_GetMaskData(GenTree* tree, optCSE_MaskData* pMaskData);

    // Given a binary tree node return true if it is safe to swap the order of evaluation for op1 and op2.
    bool optCSE_canSwap(GenTree* firstNode, GenTree* secondNode);

    struct optCSEcostCmpEx
    {
        bool operator()(const CSEdsc* op1, const CSEdsc* op2);
    };
    struct optCSEcostCmpSz
    {
        bool operator()(const CSEdsc* op1, const CSEdsc* op2);
    };

    void optCleanupCSEs();

#ifdef DEBUG
    void optEnsureClearCSEInfo();
#endif // DEBUG

    static bool Is_Shared_Const_CSE(size_t key)
    {
        return ((key & TARGET_SIGN_BIT) != 0);
    }

    // returns the encoded key
    static size_t Encode_Shared_Const_CSE_Value(size_t key)
    {
        return TARGET_SIGN_BIT | (key >> CSE_CONST_SHARED_LOW_BITS);
    }

    // returns the original key
    static size_t Decode_Shared_Const_CSE_Value(size_t enckey)
    {
        assert(Is_Shared_Const_CSE(enckey));
        return (enckey & ~TARGET_SIGN_BIT) << CSE_CONST_SHARED_LOW_BITS;
    }

/**************************************************************************
 *                   Value Number based CSEs
 *************************************************************************/

// String to use for formatting CSE numbers. Note that this is the positive number, e.g., from GET_CSE_INDEX().
#define FMT_CSE "CSE #%02u"

public:
    PhaseStatus optOptimizeValnumCSEs();

protected:
    void     optValnumCSE_Init();
    unsigned optValnumCSE_Index(GenTree* tree, Statement* stmt);
    bool optValnumCSE_Locate();
    void optValnumCSE_InitDataFlow();
    void optValnumCSE_DataFlow();
    void optValnumCSE_Availability();
    bool optValnumCSE_Heuristic();

    bool     optDoCSE;             // True when we have found a duplicate CSE tree
    bool     optValnumCSE_phase;   // True when we are executing the optOptimizeValnumCSEs() phase
    unsigned optCSECandidateCount; // Count of CSE's candidates
    unsigned optCSEstart;          // The first local variable number that is a CSE
    unsigned optCSEcount;          // The total count of CSE's introduced.
    weight_t optCSEweight;         // The weight of the current block when we are doing PerformCSE

    bool optIsCSEcandidate(GenTree* tree);

    // lclNumIsTrueCSE returns true if the LclVar was introduced by the CSE phase of the compiler
    //
    bool lclNumIsTrueCSE(unsigned lclNum) const
    {
        return ((optCSEcount > 0) && (lclNum >= optCSEstart) && (lclNum < optCSEstart + optCSEcount));
    }

    //  lclNumIsCSE returns true if the LclVar should be treated like a CSE with regards to constant prop.
    //
    bool lclNumIsCSE(unsigned lclNum) const
    {
        return lvaGetDesc(lclNum)->lvIsCSE;
    }

#ifdef DEBUG
    bool optConfigDisableCSE();
    bool optConfigDisableCSE2();
#endif

    void optOptimizeCSEs();

    static callInterf optCallInterf(GenTreeCall* call);

public:
    // VN based copy propagation.

    // In DEBUG builds, we'd like to know the tree that the SSA definition was pushed for.
    // While for ordinary SSA defs it will be available (as an ASG) in the SSA descriptor,
    // for locals which will use "definitions from uses", it will not be, so we store it
    // in this class instead.
    class CopyPropSsaDef
    {
        LclSsaVarDsc* m_ssaDef;
#ifdef DEBUG
        GenTree* m_defNode;
#endif
    public:
        CopyPropSsaDef(LclSsaVarDsc* ssaDef, GenTree* defNode)
            : m_ssaDef(ssaDef)
#ifdef DEBUG
            , m_defNode(defNode)
#endif
        {
        }

        LclSsaVarDsc* GetSsaDef() const
        {
            return m_ssaDef;
        }

#ifdef DEBUG
        GenTree* GetDefNode() const
        {
            return m_defNode;
        }
#endif
    };

    typedef ArrayStack<CopyPropSsaDef> CopyPropSsaDefStack;
    typedef JitHashTable<unsigned, JitSmallPrimitiveKeyFuncs<unsigned>, CopyPropSsaDefStack*> LclNumToLiveDefsMap;

    // Copy propagation functions.
    bool optCopyProp(BasicBlock*          block,
                     Statement*           stmt,
                     GenTreeLclVarCommon* tree,
                     unsigned             lclNum,
                     LclNumToLiveDefsMap* curSsaName);
    void optBlockCopyPropPopStacks(BasicBlock* block, LclNumToLiveDefsMap* curSsaName);
    bool optBlockCopyProp(BasicBlock* block, LclNumToLiveDefsMap* curSsaName);
    void optCopyPropPushDef(GenTree* defNode, GenTreeLclVarCommon* lclNode, LclNumToLiveDefsMap* curSsaName);
    int optCopyProp_LclVarScore(const LclVarDsc* lclVarDsc, const LclVarDsc* copyVarDsc, bool preferOp2);
    PhaseStatus optVnCopyProp();
    INDEBUG(void optDumpCopyPropStack(LclNumToLiveDefsMap* curSsaName));

    /**************************************************************************
     *               Early value propagation
     *************************************************************************/
    struct SSAName
    {
        unsigned m_lvNum;
        unsigned m_ssaNum;

        SSAName(unsigned lvNum, unsigned ssaNum) : m_lvNum(lvNum), m_ssaNum(ssaNum)
        {
        }

        static unsigned GetHashCode(SSAName ssaNm)
        {
            return (ssaNm.m_lvNum << 16) | (ssaNm.m_ssaNum);
        }

        static bool Equals(SSAName ssaNm1, SSAName ssaNm2)
        {
            return (ssaNm1.m_lvNum == ssaNm2.m_lvNum) && (ssaNm1.m_ssaNum == ssaNm2.m_ssaNum);
        }
    };

// clang-format off

#define OMF_HAS_NEWARRAY                       0x00000001 // Method contains 'new' of an SD array
#define OMF_HAS_NEWOBJ                         0x00000002 // Method contains 'new' of an object type.
#define OMF_HAS_ARRAYREF                       0x00000004 // Method contains array element loads or stores.
#define OMF_HAS_NULLCHECK                      0x00000008 // Method contains null check.
#define OMF_HAS_FATPOINTER                     0x00000010 // Method contains call, that needs fat pointer transformation.
#define OMF_HAS_OBJSTACKALLOC                  0x00000020 // Method contains an object allocated on the stack.
#define OMF_HAS_GUARDEDDEVIRT                  0x00000040 // Method contains guarded devirtualization candidate
#define OMF_HAS_EXPRUNTIMELOOKUP               0x00000080 // Method contains a runtime lookup to an expandable dictionary.
#define OMF_HAS_PATCHPOINT                     0x00000100 // Method contains patchpoints
#define OMF_NEEDS_GCPOLLS                      0x00000200 // Method needs GC polls
#define OMF_HAS_FROZEN_OBJECTS                 0x00000400 // Method has frozen objects (REF constant int)
#define OMF_HAS_PARTIAL_COMPILATION_PATCHPOINT 0x00000800 // Method contains partial compilation patchpoints
#define OMF_HAS_TAILCALL_SUCCESSOR             0x00001000 // Method has potential tail call in a non BBJ_RETURN block
#define OMF_HAS_MDNEWARRAY                     0x00002000 // Method contains 'new' of an MD array
#define OMF_HAS_MDARRAYREF                     0x00004000 // Method contains multi-dimensional intrinsic array element loads or stores.

    // clang-format on

    bool doesMethodHaveFatPointer()
    {
        return (optMethodFlags & OMF_HAS_FATPOINTER) != 0;
    }

    void setMethodHasFatPointer()
    {
        optMethodFlags |= OMF_HAS_FATPOINTER;
    }

    void clearMethodHasFatPointer()
    {
        optMethodFlags &= ~OMF_HAS_FATPOINTER;
    }

    void addFatPointerCandidate(GenTreeCall* call);

    bool doesMethodHaveFrozenObjects() const
    {
        return (optMethodFlags & OMF_HAS_FROZEN_OBJECTS) != 0;
    }

    void setMethodHasFrozenObjects()
    {
        optMethodFlags |= OMF_HAS_FROZEN_OBJECTS;
    }

    bool doesMethodHaveGuardedDevirtualization() const
    {
        return (optMethodFlags & OMF_HAS_GUARDEDDEVIRT) != 0;
    }

    void setMethodHasGuardedDevirtualization()
    {
        optMethodFlags |= OMF_HAS_GUARDEDDEVIRT;
    }

    void pickGDV(GenTreeCall*           call,
                 IL_OFFSET              ilOffset,
                 bool                   isInterface,
                 CORINFO_CLASS_HANDLE*  classGuess,
                 CORINFO_METHOD_HANDLE* methodGuess,
                 unsigned*              likelihood);

    void considerGuardedDevirtualization(GenTreeCall*            call,
                                         IL_OFFSET               ilOffset,
                                         bool                    isInterface,
                                         CORINFO_METHOD_HANDLE   baseMethod,
                                         CORINFO_CLASS_HANDLE    baseClass,
                                         CORINFO_CONTEXT_HANDLE* pContextHandle);

    bool isCompatibleMethodGDV(GenTreeCall* call, CORINFO_METHOD_HANDLE gdvTarget);

    void addGuardedDevirtualizationCandidate(GenTreeCall*          call,
                                             CORINFO_METHOD_HANDLE methodHandle,
                                             CORINFO_CLASS_HANDLE  classHandle,
                                             unsigned              methodAttr,
                                             unsigned              classAttr,
                                             unsigned              likelihood);

    bool doesMethodHaveExpRuntimeLookup()
    {
        return (optMethodFlags & OMF_HAS_EXPRUNTIMELOOKUP) != 0;
    }

    void setMethodHasExpRuntimeLookup()
    {
        optMethodFlags |= OMF_HAS_EXPRUNTIMELOOKUP;
    }

    void clearMethodHasExpRuntimeLookup()
    {
        optMethodFlags &= ~OMF_HAS_EXPRUNTIMELOOKUP;
    }

    void addExpRuntimeLookupCandidate(GenTreeCall* call);

    bool doesMethodHavePatchpoints()
    {
        return (optMethodFlags & OMF_HAS_PATCHPOINT) != 0;
    }

    void setMethodHasPatchpoint()
    {
        optMethodFlags |= OMF_HAS_PATCHPOINT;
    }

    bool doesMethodHavePartialCompilationPatchpoints()
    {
        return (optMethodFlags & OMF_HAS_PARTIAL_COMPILATION_PATCHPOINT) != 0;
    }

    void setMethodHasPartialCompilationPatchpoint()
    {
        optMethodFlags |= OMF_HAS_PARTIAL_COMPILATION_PATCHPOINT;
    }

    unsigned optMethodFlags;

    bool doesMethodHaveNoReturnCalls()
    {
        return optNoReturnCallCount > 0;
    }

    void setMethodHasNoReturnCalls()
    {
        optNoReturnCallCount++;
    }

    unsigned optNoReturnCallCount;

    // Recursion bound controls how far we can go backwards tracking for a SSA value.
    // No throughput diff was found with backward walk bound between 3-8.
    static const int optEarlyPropRecurBound = 5;

    enum class optPropKind
    {
        OPK_INVALID,
        OPK_ARRAYLEN,
        OPK_NULLCHECK
    };

    typedef JitHashTable<unsigned, JitSmallPrimitiveKeyFuncs<unsigned>, GenTree*> LocalNumberToNullCheckTreeMap;

    GenTree* getArrayLengthFromAllocation(GenTree* tree DEBUGARG(BasicBlock* block));
    GenTree* optPropGetValueRec(unsigned lclNum, unsigned ssaNum, optPropKind valueKind, int walkDepth);
    GenTree* optPropGetValue(unsigned lclNum, unsigned ssaNum, optPropKind valueKind);
    GenTree* optEarlyPropRewriteTree(GenTree* tree, LocalNumberToNullCheckTreeMap* nullCheckMap);
    bool optDoEarlyPropForBlock(BasicBlock* block);
    bool        optDoEarlyPropForFunc();
    PhaseStatus optEarlyProp();
    bool optFoldNullCheck(GenTree* tree, LocalNumberToNullCheckTreeMap* nullCheckMap);
    GenTree* optFindNullCheckToFold(GenTree* tree, LocalNumberToNullCheckTreeMap* nullCheckMap);
    bool optIsNullCheckFoldingLegal(GenTree*    tree,
                                    GenTree*    nullCheckTree,
                                    GenTree**   nullCheckParent,
                                    Statement** nullCheckStmt);
    bool optCanMoveNullCheckPastTree(GenTree* tree,
                                     unsigned nullCheckLclNum,
                                     bool     isInsideTry,
                                     bool     checkSideEffectSummary);
#if DEBUG
    void optCheckFlagsAreSet(unsigned    methodFlag,
                             const char* methodFlagStr,
                             unsigned    bbFlag,
                             const char* bbFlagStr,
                             GenTree*    tree,
                             BasicBlock* basicBlock);
#endif

    // Redundant branch opts
    //
    PhaseStatus optRedundantBranches();
    bool optRedundantRelop(BasicBlock* const block);
    bool optRedundantBranch(BasicBlock* const block);
    bool optJumpThreadDom(BasicBlock* const block, BasicBlock* const domBlock, bool domIsSameRelop);
    bool optJumpThreadPhi(BasicBlock* const block, GenTree* tree, ValueNum treeNormVN);
    bool optJumpThreadCheck(BasicBlock* const block, BasicBlock* const domBlock);
    bool optJumpThreadCore(JumpThreadInfo& jti);
    bool optReachable(BasicBlock* const fromBlock, BasicBlock* const toBlock, BasicBlock* const excludedBlock);
    BitVecTraits* optReachableBitVecTraits;
    BitVec        optReachableBitVec;
    void optRelopImpliesRelop(RelopImplicationInfo* rii);

    /**************************************************************************
     *               Value/Assertion propagation
     *************************************************************************/
public:
    // Data structures for assertion prop
    BitVecTraits* apTraits;
    ASSERT_TP     apFull;

    enum optAssertionKind
    {
        OAK_INVALID,
        OAK_EQUAL,
        OAK_NOT_EQUAL,
        OAK_SUBRANGE,
        OAK_NO_THROW,
        OAK_COUNT
    };

    enum optOp1Kind
    {
        O1K_INVALID,
        O1K_LCLVAR,
        O1K_ARR_BND,
        O1K_BOUND_OPER_BND,
        O1K_BOUND_LOOP_BND,
        O1K_CONSTANT_LOOP_BND,
        O1K_CONSTANT_LOOP_BND_UN,
        O1K_EXACT_TYPE,
        O1K_SUBTYPE,
        O1K_VALUE_NUMBER,
        O1K_COUNT
    };

    enum optOp2Kind
    {
        O2K_INVALID,
        O2K_LCLVAR_COPY,
        O2K_IND_CNS_INT,
        O2K_CONST_INT,
        O2K_CONST_LONG,
        O2K_CONST_DOUBLE,
        O2K_ZEROOBJ,
        O2K_SUBRANGE,
        O2K_COUNT
    };

    struct AssertionDsc
    {
        optAssertionKind assertionKind;
        struct SsaVar
        {
            unsigned lclNum; // assigned to or property of this local var number
            unsigned ssaNum;
        };
        struct ArrBnd
        {
            ValueNum vnIdx;
            ValueNum vnLen;
        };
        struct AssertionDscOp1
        {
            optOp1Kind kind; // a normal LclVar, or Exact-type or Subtype
            ValueNum   vn;
            union {
                SsaVar lcl;
                ArrBnd bnd;
            };
        } op1;
        struct AssertionDscOp2
        {
            optOp2Kind kind; // a const or copy assignment
            ValueNum   vn;
            struct IntVal
            {
                ssize_t iconVal; // integer
#if !defined(HOST_64BIT)
                unsigned padding; // unused; ensures iconFlags does not overlap lconVal
#endif
                GenTreeFlags iconFlags; // gtFlags
            };
            union {
                SsaVar        lcl;
                IntVal        u1;
                __int64       lconVal;
                double        dconVal;
                IntegralRange u2;
            };
        } op2;

        bool IsCheckedBoundArithBound()
        {
            return ((assertionKind == OAK_EQUAL || assertionKind == OAK_NOT_EQUAL) && op1.kind == O1K_BOUND_OPER_BND);
        }
        bool IsCheckedBoundBound()
        {
            return ((assertionKind == OAK_EQUAL || assertionKind == OAK_NOT_EQUAL) && op1.kind == O1K_BOUND_LOOP_BND);
        }
        bool IsConstantBound()
        {
            return ((assertionKind == OAK_EQUAL || assertionKind == OAK_NOT_EQUAL) &&
                    (op1.kind == O1K_CONSTANT_LOOP_BND));
        }
        bool IsConstantBoundUnsigned()
        {
            return ((assertionKind == OAK_EQUAL || assertionKind == OAK_NOT_EQUAL) &&
                    (op1.kind == O1K_CONSTANT_LOOP_BND_UN));
        }
        bool IsBoundsCheckNoThrow()
        {
            return ((assertionKind == OAK_NO_THROW) && (op1.kind == O1K_ARR_BND));
        }

        bool IsCopyAssertion()
        {
            return ((assertionKind == OAK_EQUAL) && (op1.kind == O1K_LCLVAR) && (op2.kind == O2K_LCLVAR_COPY));
        }

        bool IsConstantInt32Assertion()
        {
            return ((assertionKind == OAK_EQUAL) || (assertionKind == OAK_NOT_EQUAL)) && (op2.kind == O2K_CONST_INT);
        }

        bool CanPropLclVar()
        {
            return assertionKind == OAK_EQUAL && op1.kind == O1K_LCLVAR;
        }

        bool CanPropEqualOrNotEqual()
        {
            return assertionKind == OAK_EQUAL || assertionKind == OAK_NOT_EQUAL;
        }

        bool CanPropNonNull()
        {
            return assertionKind == OAK_NOT_EQUAL && op2.vn == ValueNumStore::VNForNull();
        }

        bool CanPropBndsCheck()
        {
            return op1.kind == O1K_ARR_BND;
        }

        bool CanPropSubRange()
        {
            return assertionKind == OAK_SUBRANGE && op1.kind == O1K_LCLVAR;
        }

        static bool SameKind(AssertionDsc* a1, AssertionDsc* a2)
        {
            return a1->assertionKind == a2->assertionKind && a1->op1.kind == a2->op1.kind &&
                   a1->op2.kind == a2->op2.kind;
        }

        static bool ComplementaryKind(optAssertionKind kind, optAssertionKind kind2)
        {
            if (kind == OAK_EQUAL)
            {
                return kind2 == OAK_NOT_EQUAL;
            }
            else if (kind == OAK_NOT_EQUAL)
            {
                return kind2 == OAK_EQUAL;
            }
            return false;
        }

        bool HasSameOp1(AssertionDsc* that, bool vnBased)
        {
            if (op1.kind != that->op1.kind)
            {
                return false;
            }
            else if (op1.kind == O1K_ARR_BND)
            {
                assert(vnBased);
                return (op1.bnd.vnIdx == that->op1.bnd.vnIdx) && (op1.bnd.vnLen == that->op1.bnd.vnLen);
            }
            else
            {
                return ((vnBased && (op1.vn == that->op1.vn)) ||
                        (!vnBased && (op1.lcl.lclNum == that->op1.lcl.lclNum)));
            }
        }

        bool HasSameOp2(AssertionDsc* that, bool vnBased)
        {
            if (op2.kind != that->op2.kind)
            {
                return false;
            }

            switch (op2.kind)
            {
                case O2K_IND_CNS_INT:
                case O2K_CONST_INT:
                    return ((op2.u1.iconVal == that->op2.u1.iconVal) && (op2.u1.iconFlags == that->op2.u1.iconFlags));

                case O2K_CONST_LONG:
                    return (op2.lconVal == that->op2.lconVal);

                case O2K_CONST_DOUBLE:
                    // exact match because of positive and negative zero.
                    return (memcmp(&op2.dconVal, &that->op2.dconVal, sizeof(double)) == 0);

                case O2K_ZEROOBJ:
                    return true;

                case O2K_LCLVAR_COPY:
                    return (op2.lcl.lclNum == that->op2.lcl.lclNum) &&
                           (!vnBased || (op2.lcl.ssaNum == that->op2.lcl.ssaNum));

                case O2K_SUBRANGE:
                    return op2.u2.Equals(that->op2.u2);

                case O2K_INVALID:
                    // we will return false
                    break;

                default:
                    assert(!"Unexpected value for op2.kind in AssertionDsc.");
                    break;
            }

            return false;
        }

        bool Complementary(AssertionDsc* that, bool vnBased)
        {
            return ComplementaryKind(assertionKind, that->assertionKind) && HasSameOp1(that, vnBased) &&
                   HasSameOp2(that, vnBased);
        }

        bool Equals(AssertionDsc* that, bool vnBased)
        {
            if (assertionKind != that->assertionKind)
            {
                return false;
            }
            else if (assertionKind == OAK_NO_THROW)
            {
                assert(op2.kind == O2K_INVALID);
                return HasSameOp1(that, vnBased);
            }
            else
            {
                return HasSameOp1(that, vnBased) && HasSameOp2(that, vnBased);
            }
        }
    };

protected:
    static fgWalkPreFn optAddCopiesCallback;
    static fgWalkPreFn optVNAssertionPropCurStmtVisitor;
    unsigned           optAddCopyLclNum;
    GenTree*           optAddCopyAsgnNode;

    bool optLocalAssertionProp;  // indicates that we are performing local assertion prop
    bool optAssertionPropagated; // set to true if we modified the trees
    bool optAssertionPropagatedCurrentStmt;
#ifdef DEBUG
    GenTree* optAssertionPropCurrentTree;
#endif
    AssertionIndex*            optComplementaryAssertionMap;
    JitExpandArray<ASSERT_TP>* optAssertionDep; // table that holds dependent assertions (assertions
                                                // using the value of a local var) for each local var
    AssertionDsc*  optAssertionTabPrivate;      // table that holds info about value assignments
    AssertionIndex optAssertionCount;           // total number of assertions in the assertion table
    AssertionIndex optMaxAssertionCount;
    bool           optCanPropLclVar;
    bool           optCanPropEqual;
    bool           optCanPropNonNull;
    bool           optCanPropBndsChk;
    bool           optCanPropSubRange;

public:
    void optVnNonNullPropCurStmt(BasicBlock* block, Statement* stmt, GenTree* tree);
    fgWalkResult optVNConstantPropCurStmt(BasicBlock* block, Statement* stmt, GenTree* tree);
    GenTree* optVNConstantPropOnJTrue(BasicBlock* block, GenTree* test);
    GenTree* optVNConstantPropOnTree(BasicBlock* block, GenTree* tree);
    GenTree* optExtractSideEffListFromConst(GenTree* tree);

    AssertionIndex GetAssertionCount()
    {
        return optAssertionCount;
    }
    ASSERT_TP* bbJtrueAssertionOut;
    typedef JitHashTable<ValueNum, JitSmallPrimitiveKeyFuncs<ValueNum>, ASSERT_TP> ValueNumToAssertsMap;
    ValueNumToAssertsMap* optValueNumToAsserts;

    // Assertion prop helpers.
    ASSERT_TP& GetAssertionDep(unsigned lclNum);
    AssertionDsc* optGetAssertion(AssertionIndex assertIndex);
    void optAssertionInit(bool isLocalProp);
    void optAssertionTraitsInit(AssertionIndex assertionCount);
    void optAssertionReset(AssertionIndex limit);
    void optAssertionRemove(AssertionIndex index);

    // Assertion prop data flow functions.
    PhaseStatus optAssertionPropMain();
    Statement* optVNAssertionPropCurStmt(BasicBlock* block, Statement* stmt);
    bool optIsTreeKnownIntValue(bool vnBased, GenTree* tree, ssize_t* pConstant, GenTreeFlags* pIconFlags);
    ASSERT_TP* optInitAssertionDataflowFlags();
    ASSERT_TP* optComputeAssertionGen();

    // Assertion Gen functions.
    void optAssertionGen(GenTree* tree);
    AssertionIndex optAssertionGenCast(GenTreeCast* cast);
    AssertionIndex optAssertionGenPhiDefn(GenTree* tree);
    AssertionInfo optCreateJTrueBoundsAssertion(GenTree* tree);
    AssertionInfo optAssertionGenJtrue(GenTree* tree);
    AssertionIndex optCreateJtrueAssertions(GenTree*                   op1,
                                            GenTree*                   op2,
                                            Compiler::optAssertionKind assertionKind,
                                            bool                       helperCallArgs = false);
    AssertionIndex optFindComplementary(AssertionIndex assertionIndex);
    void optMapComplementary(AssertionIndex assertionIndex, AssertionIndex index);

    // Assertion creation functions.
    AssertionIndex optCreateAssertion(GenTree*         op1,
                                      GenTree*         op2,
                                      optAssertionKind assertionKind,
                                      bool             helperCallArgs = false);

    AssertionIndex optFinalizeCreatingAssertion(AssertionDsc* assertion);
    ssize_t optCastConstantSmall(ssize_t iconVal, var_types smallType);

    bool optTryExtractSubrangeAssertion(GenTree* source, IntegralRange* pRange);

    void optCreateComplementaryAssertion(AssertionIndex assertionIndex,
                                         GenTree*       op1,
                                         GenTree*       op2,
                                         bool           helperCallArgs = false);

    bool optAssertionVnInvolvesNan(AssertionDsc* assertion);
    AssertionIndex optAddAssertion(AssertionDsc* assertion);
    void optAddVnAssertionMapping(ValueNum vn, AssertionIndex index);
#ifdef DEBUG
    void optPrintVnAssertionMapping();
#endif
    ASSERT_TP optGetVnMappedAssertions(ValueNum vn);

    // Used for respective assertion propagations.
    AssertionIndex optAssertionIsSubrange(GenTree* tree, IntegralRange range, ASSERT_VALARG_TP assertions);
    AssertionIndex optAssertionIsSubtype(GenTree* tree, GenTree* methodTableArg, ASSERT_VALARG_TP assertions);
    AssertionIndex optAssertionIsNonNullInternal(GenTree* op, ASSERT_VALARG_TP assertions DEBUGARG(bool* pVnBased));
    bool optAssertionIsNonNull(GenTree*         op,
                               ASSERT_VALARG_TP assertions DEBUGARG(bool* pVnBased) DEBUGARG(AssertionIndex* pIndex));

    AssertionIndex optGlobalAssertionIsEqualOrNotEqual(ASSERT_VALARG_TP assertions, GenTree* op1, GenTree* op2);
    AssertionIndex optGlobalAssertionIsEqualOrNotEqualZero(ASSERT_VALARG_TP assertions, GenTree* op1);
    AssertionIndex optLocalAssertionIsEqualOrNotEqual(
        optOp1Kind op1Kind, unsigned lclNum, optOp2Kind op2Kind, ssize_t cnsVal, ASSERT_VALARG_TP assertions);

    // Assertion prop for lcl var functions.
    bool optAssertionProp_LclVarTypeCheck(GenTree* tree, LclVarDsc* lclVarDsc, LclVarDsc* copyVarDsc);
    GenTree* optCopyAssertionProp(AssertionDsc*        curAssertion,
                                  GenTreeLclVarCommon* tree,
                                  Statement* stmt DEBUGARG(AssertionIndex index));
    GenTree* optConstantAssertionProp(AssertionDsc*        curAssertion,
                                      GenTreeLclVarCommon* tree,
                                      Statement* stmt DEBUGARG(AssertionIndex index));
    bool optIsProfitableToSubstitute(GenTreeLclVarCommon* lcl, BasicBlock* lclBlock, GenTree* value);
    bool optZeroObjAssertionProp(GenTree* tree, ASSERT_VALARG_TP assertions);

    // Assertion propagation functions.
    GenTree* optAssertionProp(ASSERT_VALARG_TP assertions, GenTree* tree, Statement* stmt, BasicBlock* block);
    GenTree* optAssertionProp_LclVar(ASSERT_VALARG_TP assertions, GenTreeLclVarCommon* tree, Statement* stmt);
    GenTree* optAssertionProp_LclFld(ASSERT_VALARG_TP assertions, GenTreeLclVarCommon* tree, Statement* stmt);
    GenTree* optAssertionProp_Asg(ASSERT_VALARG_TP assertions, GenTreeOp* asg, Statement* stmt);
    GenTree* optAssertionProp_Return(ASSERT_VALARG_TP assertions, GenTreeUnOp* ret, Statement* stmt);
    GenTree* optAssertionProp_Ind(ASSERT_VALARG_TP assertions, GenTree* tree, Statement* stmt);
    GenTree* optAssertionProp_Cast(ASSERT_VALARG_TP assertions, GenTreeCast* cast, Statement* stmt);
    GenTree* optAssertionProp_Call(ASSERT_VALARG_TP assertions, GenTreeCall* call, Statement* stmt);
    GenTree* optAssertionProp_RelOp(ASSERT_VALARG_TP assertions, GenTree* tree, Statement* stmt);
    GenTree* optAssertionProp_ConditionalOp(ASSERT_VALARG_TP assertions, GenTree* tree, Statement* stmt);
    GenTree* optAssertionProp_Comma(ASSERT_VALARG_TP assertions, GenTree* tree, Statement* stmt);
    GenTree* optAssertionProp_BndsChk(ASSERT_VALARG_TP assertions, GenTree* tree, Statement* stmt);
    GenTree* optAssertionPropGlobal_RelOp(ASSERT_VALARG_TP assertions, GenTree* tree, Statement* stmt);
    GenTree* optAssertionPropLocal_RelOp(ASSERT_VALARG_TP assertions, GenTree* tree, Statement* stmt);
    GenTree* optAssertionProp_Update(GenTree* newTree, GenTree* tree, Statement* stmt);
    GenTree* optNonNullAssertionProp_Call(ASSERT_VALARG_TP assertions, GenTreeCall* call);

    // Implied assertion functions.
    void optImpliedAssertions(AssertionIndex assertionIndex, ASSERT_TP& activeAssertions);
    void optImpliedByTypeOfAssertions(ASSERT_TP& activeAssertions);
    void optImpliedByCopyAssertion(AssertionDsc* copyAssertion, AssertionDsc* depAssertion, ASSERT_TP& result);
    void optImpliedByConstAssertion(AssertionDsc* curAssertion, ASSERT_TP& result);

#ifdef DEBUG
    void optPrintAssertion(AssertionDsc* newAssertion, AssertionIndex assertionIndex = 0);
    void optPrintAssertionIndex(AssertionIndex index);
    void optPrintAssertionIndices(ASSERT_TP assertions);
    void optDebugCheckAssertion(AssertionDsc* assertion);
    void optDebugCheckAssertions(AssertionIndex AssertionIndex);
#endif

    static void optDumpAssertionIndices(const char* header, ASSERT_TP assertions, const char* footer = nullptr);
    static void optDumpAssertionIndices(ASSERT_TP assertions, const char* footer = nullptr);

    PhaseStatus optAddCopies();

    /**************************************************************************
     *                          Range checks
     *************************************************************************/

public:
    struct LoopCloneVisitorInfo
    {
        LoopCloneContext* context;
        Statement*        stmt;
        const unsigned    loopNum;
        const bool        cloneForArrayBounds;
        const bool        cloneForGDVTests;
        LoopCloneVisitorInfo(LoopCloneContext* context,
                             unsigned          loopNum,
                             Statement*        stmt,
                             bool              cloneForArrayBounds,
                             bool              cloneForGDVTests)
            : context(context)
            , stmt(nullptr)
            , loopNum(loopNum)
            , cloneForArrayBounds(cloneForArrayBounds)
            , cloneForGDVTests(cloneForGDVTests)
        {
        }
    };

    bool optIsStackLocalInvariant(unsigned loopNum, unsigned lclNum);
    bool optExtractArrIndex(GenTree* tree, ArrIndex* result, unsigned lhsNum, bool* topLevelIsFinal);
    bool optReconstructArrIndexHelp(GenTree* tree, ArrIndex* result, unsigned lhsNum, bool* topLevelIsFinal);
    bool optReconstructArrIndex(GenTree* tree, ArrIndex* result);
    bool optIdentifyLoopOptInfo(unsigned loopNum, LoopCloneContext* context);
    static fgWalkPreFn optCanOptimizeByLoopCloningVisitor;
    fgWalkResult optCanOptimizeByLoopCloning(GenTree* tree, LoopCloneVisitorInfo* info);
    bool optObtainLoopCloningOpts(LoopCloneContext* context);
    bool optIsLoopClonable(unsigned loopInd);
    bool optCheckLoopCloningGDVTestProfitable(GenTreeOp* guard, LoopCloneVisitorInfo* info);
    bool optIsHandleOrIndirOfHandle(GenTree* tree, GenTreeFlags handleType);

    bool optLoopCloningEnabled();

#ifdef DEBUG
    void optDebugLogLoopCloning(BasicBlock* block, Statement* insertBefore);
#endif
    void optPerformStaticOptimizations(unsigned loopNum, LoopCloneContext* context DEBUGARG(bool fastPath));
    bool optComputeDerefConditions(unsigned loopNum, LoopCloneContext* context);
    bool optDeriveLoopCloningConditions(unsigned loopNum, LoopCloneContext* context);
    BasicBlock* optInsertLoopChoiceConditions(LoopCloneContext* context,
                                              unsigned          loopNum,
                                              BasicBlock*       slowHead,
                                              BasicBlock*       insertAfter);

protected:
    ssize_t optGetArrayRefScaleAndIndex(GenTree* mul, GenTree** pIndex DEBUGARG(bool bRngChk));

    bool optReachWithoutCall(BasicBlock* srcBB, BasicBlock* dstBB);

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX                           RegAlloc                                        XX
    XX                                                                           XX
    XX  Does the register allocation and puts the remaining lclVars on the stack XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */

public:
    regNumber raUpdateRegStateForArg(RegState* regState, LclVarDsc* argDsc);

    void raMarkStkVars();

#if FEATURE_PARTIAL_SIMD_CALLEE_SAVE
#if defined(TARGET_AMD64)
    static bool varTypeNeedsPartialCalleeSave(var_types type)
    {
        assert(type != TYP_STRUCT);
        return (type == TYP_SIMD32);
    }
#elif defined(TARGET_ARM64)
    static bool varTypeNeedsPartialCalleeSave(var_types type)
    {
        assert(type != TYP_STRUCT);
        // ARM64 ABI FP Callee save registers only require Callee to save lower 8 Bytes
        // For SIMD types longer than 8 bytes Caller is responsible for saving and restoring Upper bytes.
        return ((type == TYP_SIMD16) || (type == TYP_SIMD12));
    }
#else // !defined(TARGET_AMD64) && !defined(TARGET_ARM64)
#error("Unknown target architecture for FEATURE_SIMD")
#endif // !defined(TARGET_AMD64) && !defined(TARGET_ARM64)
#endif // FEATURE_PARTIAL_SIMD_CALLEE_SAVE

protected:
    // Some things are used by both LSRA and regpredict allocators.

    FrameType rpFrameType;
    bool      rpMustCreateEBPCalled; // Set to true after we have called rpMustCreateEBPFrame once

    bool rpMustCreateEBPFrame(INDEBUG(const char** wbReason));

private:
    Lowering*            m_pLowering;   // Lowering; needed to Lower IR that's added or modified after Lowering.
    LinearScanInterface* m_pLinearScan; // Linear Scan allocator

    /* raIsVarargsStackArg is called by raMaskStkVars and by
       lvaComputeRefCounts.  It identifies the special case
       where a varargs function has a parameter passed on the
       stack, other than the special varargs handle.  Such parameters
       require special treatment, because they cannot be tracked
       by the GC (their offsets in the stack are not known
       at compile time).
    */

    bool raIsVarargsStackArg(unsigned lclNum)
    {
#ifdef TARGET_X86

        LclVarDsc* varDsc = lvaGetDesc(lclNum);

        assert(varDsc->lvIsParam);

        return (info.compIsVarArgs && !varDsc->lvIsRegArg && (lclNum != lvaVarargsHandleArg));

#else // TARGET_X86

        return false;

#endif // TARGET_X86
    }

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX                           EEInterface                                     XX
    XX                                                                           XX
    XX   Get to the class and method info from the Execution Engine given        XX
    XX   tokens for the class and method                                         XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */

public:
    // Get handles

    void eeGetCallInfo(CORINFO_RESOLVED_TOKEN* pResolvedToken,
                       CORINFO_RESOLVED_TOKEN* pConstrainedToken,
                       CORINFO_CALLINFO_FLAGS  flags,
                       CORINFO_CALL_INFO*      pResult);

    void eeGetFieldInfo(CORINFO_RESOLVED_TOKEN* pResolvedToken,
                        CORINFO_ACCESS_FLAGS    flags,
                        CORINFO_FIELD_INFO*     pResult);

    // Get the flags

    bool eeIsValueClass(CORINFO_CLASS_HANDLE clsHnd);
    bool eeIsIntrinsic(CORINFO_METHOD_HANDLE ftn);
    bool eeIsFieldStatic(CORINFO_FIELD_HANDLE fldHnd);

    var_types eeGetFieldType(CORINFO_FIELD_HANDLE fldHnd, CORINFO_CLASS_HANDLE* pStructHnd = nullptr);

    void eePrintJitType(class StringPrinter* printer, var_types jitType);
    void eePrintType(class StringPrinter* printer,
                     CORINFO_CLASS_HANDLE clsHnd,
                     bool                 includeNamespaces,
                     bool                 includeInstantiation);
    void eePrintTypeOrJitAlias(class StringPrinter* printer,
                               CORINFO_CLASS_HANDLE clsHnd,
                               bool                 includeNamespaces,
                               bool                 includeInstantiation);
    void eePrintMethod(class StringPrinter*  printer,
                       CORINFO_CLASS_HANDLE  clsHnd,
                       CORINFO_METHOD_HANDLE methodHnd,
                       CORINFO_SIG_INFO*     sig,
                       bool                  includeNamespaces,
                       bool                  includeClassInstantiation,
                       bool                  includeMethodInstantiation,
                       bool                  includeSignature,
                       bool                  includeReturnType,
                       bool                  includeThisSpecifier);

#if defined(DEBUG) || defined(FEATURE_JIT_METHOD_PERF) || defined(FEATURE_SIMD) || defined(TRACK_LSRA_STATS)
    const char* eeGetMethodName(CORINFO_METHOD_HANDLE hnd, const char** className);
    const char* eeGetMethodFullName(CORINFO_METHOD_HANDLE hnd,
                                    bool                  includeReturnType    = true,
                                    bool                  includeThisSpecifier = true);
    unsigned compMethodHash(CORINFO_METHOD_HANDLE methodHandle);

    bool eeIsNativeMethod(CORINFO_METHOD_HANDLE method);
    CORINFO_METHOD_HANDLE eeGetMethodHandleForNative(CORINFO_METHOD_HANDLE method);
#endif

    var_types eeGetArgType(CORINFO_ARG_LIST_HANDLE list, CORINFO_SIG_INFO* sig);
    var_types eeGetArgType(CORINFO_ARG_LIST_HANDLE list, CORINFO_SIG_INFO* sig, bool* isPinned);
    CORINFO_CLASS_HANDLE eeGetArgClass(CORINFO_SIG_INFO* sig, CORINFO_ARG_LIST_HANDLE list);
    CORINFO_CLASS_HANDLE eeGetClassFromContext(CORINFO_CONTEXT_HANDLE context);
    unsigned eeGetArgSize(CORINFO_ARG_LIST_HANDLE list, CORINFO_SIG_INFO* sig);
    static unsigned eeGetArgSizeAlignment(var_types type, bool isFloatHfa);

    // VOM info, method sigs

    void eeGetSig(unsigned               sigTok,
                  CORINFO_MODULE_HANDLE  scope,
                  CORINFO_CONTEXT_HANDLE context,
                  CORINFO_SIG_INFO*      retSig);

    void eeGetCallSiteSig(unsigned               sigTok,
                          CORINFO_MODULE_HANDLE  scope,
                          CORINFO_CONTEXT_HANDLE context,
                          CORINFO_SIG_INFO*      retSig);

    void eeGetMethodSig(CORINFO_METHOD_HANDLE methHnd, CORINFO_SIG_INFO* retSig, CORINFO_CLASS_HANDLE owner = nullptr);

    // Method entry-points, instrs

    CORINFO_METHOD_HANDLE eeMarkNativeTarget(CORINFO_METHOD_HANDLE method);

    CORINFO_EE_INFO eeInfo;
    bool            eeInfoInitialized;

    CORINFO_EE_INFO* eeGetEEInfo();

    // Gets the offset of a SDArray's first element
    static unsigned eeGetArrayDataOffset();

    // Get the offset of a MDArray's first element
    static unsigned eeGetMDArrayDataOffset(unsigned rank);

    // Get the offset of a MDArray's dimension length for a given dimension.
    static unsigned eeGetMDArrayLengthOffset(unsigned rank, unsigned dimension);

    // Get the offset of a MDArray's lower bound for a given dimension.
    static unsigned eeGetMDArrayLowerBoundOffset(unsigned rank, unsigned dimension);

    GenTree* eeGetPInvokeCookie(CORINFO_SIG_INFO* szMetaSig);

    // Returns the page size for the target machine as reported by the EE.
    target_size_t eeGetPageSize()
    {
        return (target_size_t)eeGetEEInfo()->osPageSize;
    }

    //------------------------------------------------------------------------
    // VirtualStubParam: virtual stub dispatch extra parameter (slot address).
    //
    // It represents Abi and target specific registers for the parameter.
    //
    class VirtualStubParamInfo
    {
    public:
        VirtualStubParamInfo(bool isNativeAOT)
        {
#if defined(TARGET_X86)
            reg     = REG_EAX;
            regMask = RBM_EAX;
#elif defined(TARGET_AMD64)
            if (isNativeAOT)
            {
                reg     = REG_R10;
                regMask = RBM_R10;
            }
            else
            {
                reg     = REG_R11;
                regMask = RBM_R11;
            }
#elif defined(TARGET_ARM)
            if (isNativeAOT)
            {
                reg     = REG_R12;
                regMask = RBM_R12;
            }
            else
            {
                reg     = REG_R4;
                regMask = RBM_R4;
            }
#elif defined(TARGET_ARM64)
            reg     = REG_R11;
            regMask = RBM_R11;
#elif defined(TARGET_LOONGARCH64)
            reg     = REG_T8;
            regMask = RBM_T8;
#else
#error Unsupported or unset target architecture
#endif
        }

        regNumber GetReg() const
        {
            return reg;
        }

        _regMask_enum GetRegMask() const
        {
            return regMask;
        }

    private:
        regNumber     reg;
        _regMask_enum regMask;
    };

    VirtualStubParamInfo* virtualStubParamInfo;

    bool IsTargetAbi(CORINFO_RUNTIME_ABI abi)
    {
        return eeGetEEInfo()->targetAbi == abi;
    }

    bool generateCFIUnwindCodes()
    {
#if defined(FEATURE_CFI_SUPPORT)
        return TargetOS::IsUnix && IsTargetAbi(CORINFO_NATIVEAOT_ABI);
#else
        return false;
#endif
    }

    // Debugging support - Line number info

    void eeGetStmtOffsets();

    unsigned eeBoundariesCount;

    ICorDebugInfo::OffsetMapping* eeBoundaries; // Boundaries to report to the EE
    void eeSetLIcount(unsigned count);
    void eeSetLIinfo(unsigned which, UNATIVE_OFFSET offs, IPmappingDscKind kind, const ILLocation& loc);
    void eeSetLIdone();

#ifdef DEBUG
    static void eeDispILOffs(IL_OFFSET offs);
    static void eeDispSourceMappingOffs(uint32_t offs);
    static void eeDispLineInfo(const ICorDebugInfo::OffsetMapping* line);
    void eeDispLineInfos();
#endif // DEBUG

    // Debugging support - Local var info

    void eeGetVars();

    unsigned eeVarsCount;

    struct VarResultInfo
    {
        UNATIVE_OFFSET             startOffset;
        UNATIVE_OFFSET             endOffset;
        DWORD                      varNumber;
        CodeGenInterface::siVarLoc loc;
    } * eeVars;
    void eeSetLVcount(unsigned count);
    void eeSetLVinfo(unsigned                          which,
                     UNATIVE_OFFSET                    startOffs,
                     UNATIVE_OFFSET                    length,
                     unsigned                          varNum,
                     const CodeGenInterface::siVarLoc& loc);
    void eeSetLVdone();

#ifdef DEBUG
    void eeDispVar(ICorDebugInfo::NativeVarInfo* var);
    void eeDispVars(CORINFO_METHOD_HANDLE ftn, ULONG32 cVars, ICorDebugInfo::NativeVarInfo* vars);
#endif // DEBUG

    // ICorJitInfo wrappers

    void eeAllocMem(AllocMemArgs* args, const UNATIVE_OFFSET roDataSectionAlignment);

    void eeReserveUnwindInfo(bool isFunclet, bool isColdCode, ULONG unwindSize);

    void eeAllocUnwindInfo(BYTE*          pHotCode,
                           BYTE*          pColdCode,
                           ULONG          startOffset,
                           ULONG          endOffset,
                           ULONG          unwindSize,
                           BYTE*          pUnwindBlock,
                           CorJitFuncKind funcKind);

    void eeSetEHcount(unsigned cEH);

    void eeSetEHinfo(unsigned EHnumber, const CORINFO_EH_CLAUSE* clause);

    WORD eeGetRelocTypeHint(void* target);

    // ICorStaticInfo wrapper functions

    bool eeTryResolveToken(CORINFO_RESOLVED_TOKEN* resolvedToken);

#if defined(UNIX_AMD64_ABI)
#ifdef DEBUG
    static void dumpSystemVClassificationType(SystemVClassificationType ct);
#endif // DEBUG

    void eeGetSystemVAmd64PassStructInRegisterDescriptor(
        /*IN*/ CORINFO_CLASS_HANDLE                                  structHnd,
        /*OUT*/ SYSTEMV_AMD64_CORINFO_STRUCT_REG_PASSING_DESCRIPTOR* structPassInRegDescPtr);
#endif // UNIX_AMD64_ABI

    template <typename ParamType>
    bool eeRunWithErrorTrap(void (*function)(ParamType*), ParamType* param)
    {
        return eeRunWithErrorTrapImp(reinterpret_cast<void (*)(void*)>(function), reinterpret_cast<void*>(param));
    }

    bool eeRunWithErrorTrapImp(void (*function)(void*), void* param);

    template <typename ParamType>
    bool eeRunWithSPMIErrorTrap(void (*function)(ParamType*), ParamType* param)
    {
        return eeRunWithSPMIErrorTrapImp(reinterpret_cast<void (*)(void*)>(function), reinterpret_cast<void*>(param));
    }

    template <typename Functor>
    bool eeRunFunctorWithSPMIErrorTrap(Functor f)
    {
        return eeRunWithSPMIErrorTrap<Functor>([](Functor* pf) { (*pf)(); }, &f);
    }

    bool eeRunWithSPMIErrorTrapImp(void (*function)(void*), void* param);

    // Utility functions

    const char* eeGetFieldName(CORINFO_FIELD_HANDLE fieldHnd, const char** classNamePtr = nullptr);

#if defined(DEBUG)
    void eePrintObjectDescription(const char* prefix, CORINFO_OBJECT_HANDLE handle);
    unsigned eeTryGetClassSize(CORINFO_CLASS_HANDLE clsHnd);
    const char16_t* eeGetShortClassName(CORINFO_CLASS_HANDLE clsHnd);
#endif

    const char* eeGetClassName(CORINFO_CLASS_HANDLE clsHnd);

    static CORINFO_METHOD_HANDLE eeFindHelper(unsigned helper);
    static CorInfoHelpFunc eeGetHelperNum(CORINFO_METHOD_HANDLE method);

    static bool IsSharedStaticHelper(GenTree* tree);
    static bool IsGcSafePoint(GenTreeCall* call);

    static CORINFO_FIELD_HANDLE eeFindJitDataOffs(unsigned jitDataOffs);
    // returns true/false if 'field' is a Jit Data offset
    static bool eeIsJitDataOffs(CORINFO_FIELD_HANDLE field);
    // returns a number < 0 if 'field' is not a Jit Data offset, otherwise the data offset (limited to 2GB)
    static int eeGetJitDataOffs(CORINFO_FIELD_HANDLE field);

    /*****************************************************************************/

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX                           CodeGenerator                                   XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */

public:
    CodeGenInterface* codeGen;

    // Record the instr offset mapping to the generated code

    jitstd::list<IPmappingDsc>  genIPmappings;
    jitstd::list<RichIPMapping> genRichIPmappings;

    // Managed RetVal - A side hash table meant to record the mapping from a
    // GT_CALL node to its debug info.  This info is used to emit sequence points
    // that can be used by debugger to determine the native offset at which the
    // managed RetVal will be available.
    //
    // In fact we can store debug info in a GT_CALL node.  This was ruled out in
    // favor of a side table for two reasons: 1) We need debug info for only those
    // GT_CALL nodes (created during importation) that correspond to an IL call and
    // whose return type is other than TYP_VOID. 2) GT_CALL node is a frequently used
    // structure and IL offset is needed only when generating debuggable code. Therefore
    // it is desirable to avoid memory size penalty in retail scenarios.
    typedef JitHashTable<GenTree*, JitPtrKeyFuncs<GenTree>, DebugInfo> CallSiteDebugInfoTable;
    CallSiteDebugInfoTable* genCallSite2DebugInfoMap;

    unsigned    genReturnLocal; // Local number for the return value when applicable.
    BasicBlock* genReturnBB;    // jumped to when not optimizing for speed.

    // The following properties are part of CodeGenContext.  Getters are provided here for
    // convenience and backward compatibility, but the properties can only be set by invoking
    // the setter on CodeGenContext directly.

    emitter* GetEmitter() const
    {
        return codeGen->GetEmitter();
    }

    bool isFramePointerUsed() const
    {
        return codeGen->isFramePointerUsed();
    }

    bool GetInterruptible()
    {
        return codeGen->GetInterruptible();
    }
    void SetInterruptible(bool value)
    {
        codeGen->SetInterruptible(value);
    }

#if DOUBLE_ALIGN
    const bool genDoubleAlign()
    {
        return codeGen->doDoubleAlign();
    }
    DWORD getCanDoubleAlign();
    bool shouldDoubleAlign(unsigned refCntStk,
                           unsigned refCntReg,
                           weight_t refCntWtdReg,
                           unsigned refCntStkParam,
                           weight_t refCntWtdStkDbl);
#endif // DOUBLE_ALIGN

    bool IsFullPtrRegMapRequired()
    {
        return codeGen->IsFullPtrRegMapRequired();
    }
    void SetFullPtrRegMapRequired(bool value)
    {
        codeGen->SetFullPtrRegMapRequired(value);
    }

// Things that MAY belong either in CodeGen or CodeGenContext

#if defined(FEATURE_EH_FUNCLETS)
    FuncInfoDsc*   compFuncInfos;
    unsigned short compCurrFuncIdx;
    unsigned short compFuncInfoCount;

    unsigned short compFuncCount()
    {
        assert(fgFuncletsCreated);
        return compFuncInfoCount;
    }

#else // !FEATURE_EH_FUNCLETS

    // This is a no-op when there are no funclets!
    void genUpdateCurrentFunclet(BasicBlock* block)
    {
        return;
    }

    FuncInfoDsc compFuncInfoRoot;

    static const unsigned compCurrFuncIdx = 0;

    unsigned short compFuncCount()
    {
        return 1;
    }

#endif // !FEATURE_EH_FUNCLETS

    FuncInfoDsc* funCurrentFunc();
    void funSetCurrentFunc(unsigned funcIdx);
    FuncInfoDsc* funGetFunc(unsigned funcIdx);
    unsigned int funGetFuncIdx(BasicBlock* block);

    // LIVENESS

    VARSET_TP compCurLife;     // current live variables
    GenTree*  compCurLifeTree; // node after which compCurLife has been computed

    // Compare the given "newLife" with last set of live variables and update
    // codeGen "gcInfo", siScopes, "regSet" with the new variable's homes/liveness.
    template <bool ForCodeGen>
    void compChangeLife(VARSET_VALARG_TP newLife);

    // Update the GC's masks, register's masks and reports change on variable's homes given a set of
    // current live variables if changes have happened since "compCurLife".
    template <bool ForCodeGen>
    inline void compUpdateLife(VARSET_VALARG_TP newLife);

    // Gets a register mask that represent the kill set for a helper call since
    // not all JIT Helper calls follow the standard ABI on the target architecture.
    regMaskTP compHelperCallKillSet(CorInfoHelpFunc helper);

    // If "tree" is a indirection (GT_IND, or GT_OBJ) whose arg is an ADDR, whose arg is a LCL_VAR, return that LCL_VAR
    // node, else NULL.
    static GenTreeLclVar* fgIsIndirOfAddrOfLocal(GenTree* tree);

    // This map is indexed by GT_OBJ nodes that are address of promoted struct variables, which
    // have been annotated with the GTF_VAR_DEATH flag.  If such a node is *not* mapped in this
    // table, one may assume that all the (tracked) field vars die at this GT_OBJ.  Otherwise,
    // the node maps to a pointer to a VARSET_TP, containing set bits for each of the tracked field
    // vars of the promoted struct local that go dead at the given node (the set bits are the bits
    // for the tracked var indices of the field vars, as in a live var set).
    //
    // The map is allocated on demand so all map operations should use one of the following three
    // wrapper methods.

    NodeToVarsetPtrMap* m_promotedStructDeathVars;

    NodeToVarsetPtrMap* GetPromotedStructDeathVars()
    {
        if (m_promotedStructDeathVars == nullptr)
        {
            m_promotedStructDeathVars = new (getAllocator()) NodeToVarsetPtrMap(getAllocator());
        }
        return m_promotedStructDeathVars;
    }

    void ClearPromotedStructDeathVars()
    {
        if (m_promotedStructDeathVars != nullptr)
        {
            m_promotedStructDeathVars->RemoveAll();
        }
    }

    bool LookupPromotedStructDeathVars(GenTree* tree, VARSET_TP** bits)
    {
        *bits       = nullptr;
        bool result = false;

        if (m_promotedStructDeathVars != nullptr)
        {
            result = m_promotedStructDeathVars->Lookup(tree, bits);
        }

        return result;
    }

/*
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XX                                                                           XX
XX                           UnwindInfo                                      XX
XX                                                                           XX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
*/

#if !defined(__GNUC__)
#pragma region Unwind information
#endif

public:
    //
    // Infrastructure functions: start/stop/reserve/emit.
    //

    void unwindBegProlog();
    void unwindEndProlog();
    void unwindBegEpilog();
    void unwindEndEpilog();
    void unwindReserve();
    void unwindEmit(void* pHotCode, void* pColdCode);

    //
    // Specific unwind information functions: called by code generation to indicate a particular
    // prolog or epilog unwindable instruction has been generated.
    //

    void unwindPush(regNumber reg);
    void unwindAllocStack(unsigned size);
    void unwindSetFrameReg(regNumber reg, unsigned offset);
    void unwindSaveReg(regNumber reg, unsigned offset);

#if defined(TARGET_ARM)
    void unwindPushMaskInt(regMaskTP mask);
    void unwindPushMaskFloat(regMaskTP mask);
    void unwindPopMaskInt(regMaskTP mask);
    void unwindPopMaskFloat(regMaskTP mask);
    void unwindBranch16();                    // The epilog terminates with a 16-bit branch (e.g., "bx lr")
    void unwindNop(unsigned codeSizeInBytes); // Generate unwind NOP code. 'codeSizeInBytes' is 2 or 4 bytes. Only
                                              // called via unwindPadding().
    void unwindPadding(); // Generate a sequence of unwind NOP codes representing instructions between the last
                          // instruction and the current location.
#endif                    // TARGET_ARM

#if defined(TARGET_ARM64)
    void unwindNop();
    void unwindPadding(); // Generate a sequence of unwind NOP codes representing instructions between the last
                          // instruction and the current location.
    void unwindSaveReg(regNumber reg, int offset);                                // str reg, [sp, #offset]
    void unwindSaveRegPreindexed(regNumber reg, int offset);                      // str reg, [sp, #offset]!
    void unwindSaveRegPair(regNumber reg1, regNumber reg2, int offset);           // stp reg1, reg2, [sp, #offset]
    void unwindSaveRegPairPreindexed(regNumber reg1, regNumber reg2, int offset); // stp reg1, reg2, [sp, #offset]!
    void unwindSaveNext();                                                        // unwind code: save_next
    void unwindReturn(regNumber reg);                                             // ret lr
#endif                                                                            // defined(TARGET_ARM64)

#if defined(TARGET_LOONGARCH64)
    void unwindNop();
    void unwindPadding(); // Generate a sequence of unwind NOP codes representing instructions between the last
                          // instruction and the current location.
    void unwindSaveReg(regNumber reg, int offset);
    void unwindSaveRegPair(regNumber reg1, regNumber reg2, int offset);
    void unwindReturn(regNumber reg);
#endif // defined(TARGET_LOONGARCH64)

    //
    // Private "helper" functions for the unwind implementation.
    //

private:
#if defined(FEATURE_EH_FUNCLETS)
    void unwindGetFuncLocations(FuncInfoDsc*             func,
                                bool                     getHotSectionData,
                                /* OUT */ emitLocation** ppStartLoc,
                                /* OUT */ emitLocation** ppEndLoc);
#endif // FEATURE_EH_FUNCLETS

    void unwindReserveFunc(FuncInfoDsc* func);
    void unwindEmitFunc(FuncInfoDsc* func, void* pHotCode, void* pColdCode);

#if defined(TARGET_AMD64) || (defined(TARGET_X86) && defined(FEATURE_EH_FUNCLETS))

    void unwindReserveFuncHelper(FuncInfoDsc* func, bool isHotCode);
    void unwindEmitFuncHelper(FuncInfoDsc* func, void* pHotCode, void* pColdCode, bool isHotCode);

#endif // TARGET_AMD64 || (TARGET_X86 && FEATURE_EH_FUNCLETS)

    UNATIVE_OFFSET unwindGetCurrentOffset(FuncInfoDsc* func);

#if defined(TARGET_AMD64)

    void unwindBegPrologWindows();
    void unwindPushWindows(regNumber reg);
    void unwindAllocStackWindows(unsigned size);
    void unwindSetFrameRegWindows(regNumber reg, unsigned offset);
    void unwindSaveRegWindows(regNumber reg, unsigned offset);

#ifdef UNIX_AMD64_ABI
    void unwindSaveRegCFI(regNumber reg, unsigned offset);
#endif // UNIX_AMD64_ABI
#elif defined(TARGET_ARM)

    void unwindPushPopMaskInt(regMaskTP mask, bool useOpsize16);
    void unwindPushPopMaskFloat(regMaskTP mask);

#endif // TARGET_ARM

#if defined(FEATURE_CFI_SUPPORT)
    short mapRegNumToDwarfReg(regNumber reg);
    void createCfiCode(FuncInfoDsc* func, UNATIVE_OFFSET codeOffset, UCHAR opcode, short dwarfReg, INT offset = 0);
    void unwindPushPopCFI(regNumber reg);
    void unwindBegPrologCFI();
    void unwindPushPopMaskCFI(regMaskTP regMask, bool isFloat);
    void unwindAllocStackCFI(unsigned size);
    void unwindSetFrameRegCFI(regNumber reg, unsigned offset);
    void unwindEmitFuncCFI(FuncInfoDsc* func, void* pHotCode, void* pColdCode);
#ifdef DEBUG
    void DumpCfiInfo(bool                  isHotCode,
                     UNATIVE_OFFSET        startOffset,
                     UNATIVE_OFFSET        endOffset,
                     DWORD                 cfiCodeBytes,
                     const CFI_CODE* const pCfiCode);
#endif

#endif // FEATURE_CFI_SUPPORT

#if !defined(__GNUC__)
#pragma endregion // Note: region is NOT under !defined(__GNUC__)
#endif

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX                               SIMD                                        XX
    XX                                                                           XX
    XX   Info about SIMD types, methods and the SIMD assembly (i.e. the assembly XX
    XX   that contains the distinguished, well-known SIMD type definitions).     XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */

    bool IsBaselineSimdIsaSupported()
    {
#ifdef FEATURE_SIMD
#if defined(TARGET_XARCH)
        CORINFO_InstructionSet minimumIsa = InstructionSet_SSE2;
#elif defined(TARGET_ARM64)
        CORINFO_InstructionSet minimumIsa = InstructionSet_AdvSimd;
#elif defined(TARGET_LOONGARCH64)
        // TODO: supporting SIMD feature for LoongArch64.
        assert(!"unimplemented yet on LA");
        CORINFO_InstructionSet minimumIsa = 0;
#else
#error Unsupported platform
#endif // !TARGET_XARCH && !TARGET_ARM64 && !TARGET_LOONGARCH64

        return compOpportunisticallyDependsOn(minimumIsa);
#else
        return false;
#endif
    }

#if defined(DEBUG)
    bool IsBaselineSimdIsaSupportedDebugOnly()
    {
#ifdef FEATURE_SIMD
#if defined(TARGET_XARCH)
        CORINFO_InstructionSet minimumIsa = InstructionSet_SSE2;
#elif defined(TARGET_ARM64)
        CORINFO_InstructionSet minimumIsa = InstructionSet_AdvSimd;
#else
#error Unsupported platform
#endif // !TARGET_XARCH && !TARGET_ARM64

        return compIsaSupportedDebugOnly(minimumIsa);
#else
        return false;
#endif // FEATURE_SIMD
    }
#endif // DEBUG

    // Get highest available level for SIMD codegen
    SIMDLevel getSIMDSupportLevel()
    {
#if defined(TARGET_XARCH)
        if (compOpportunisticallyDependsOn(InstructionSet_AVX2))
        {
            return SIMD_AVX2_Supported;
        }

        if (compOpportunisticallyDependsOn(InstructionSet_SSE42))
        {
            return SIMD_SSE4_Supported;
        }

        // min bar is SSE2
        return SIMD_SSE2_Supported;
#else
        assert(!"Available instruction set(s) for SIMD codegen is not defined for target arch");
        unreached();
        return SIMD_Not_Supported;
#endif
    }

    bool isIntrinsicType(CORINFO_CLASS_HANDLE clsHnd)
    {
        return info.compCompHnd->isIntrinsicType(clsHnd);
    }

    const char* getClassNameFromMetadata(CORINFO_CLASS_HANDLE cls, const char** namespaceName)
    {
        return info.compCompHnd->getClassNameFromMetadata(cls, namespaceName);
    }

    CORINFO_CLASS_HANDLE getTypeInstantiationArgument(CORINFO_CLASS_HANDLE cls, unsigned index)
    {
        return info.compCompHnd->getTypeInstantiationArgument(cls, index);
    }

#ifdef FEATURE_SIMD
    // Have we identified any SIMD types?
    // This is currently used by struct promotion to avoid getting type information for a struct
    // field to see if it is a SIMD type, if we haven't seen any SIMD types or operations in
    // the method.
    bool _usesSIMDTypes;
    bool usesSIMDTypes()
    {
        return _usesSIMDTypes;
    }
    void setUsesSIMDTypes(bool value)
    {
        _usesSIMDTypes = value;
    }

    // This is a temp lclVar allocated on the stack as TYP_SIMD.  It is used to implement intrinsics
    // that require indexed access to the individual fields of the vector, which is not well supported
    // by the hardware.  It is allocated when/if such situations are encountered during Lowering.
    unsigned lvaSIMDInitTempVarNum;

    struct SIMDHandlesCache
    {
        // SIMD Types
        CORINFO_CLASS_HANDLE SIMDFloatHandle;
        CORINFO_CLASS_HANDLE SIMDDoubleHandle;
        CORINFO_CLASS_HANDLE SIMDIntHandle;
        CORINFO_CLASS_HANDLE SIMDUShortHandle;
        CORINFO_CLASS_HANDLE SIMDUByteHandle;
        CORINFO_CLASS_HANDLE SIMDShortHandle;
        CORINFO_CLASS_HANDLE SIMDByteHandle;
        CORINFO_CLASS_HANDLE SIMDLongHandle;
        CORINFO_CLASS_HANDLE SIMDUIntHandle;
        CORINFO_CLASS_HANDLE SIMDULongHandle;
        CORINFO_CLASS_HANDLE SIMDNIntHandle;
        CORINFO_CLASS_HANDLE SIMDNUIntHandle;

        CORINFO_CLASS_HANDLE SIMDVector2Handle;
        CORINFO_CLASS_HANDLE SIMDVector3Handle;
        CORINFO_CLASS_HANDLE SIMDVector4Handle;
        CORINFO_CLASS_HANDLE SIMDVectorHandle;

#ifdef FEATURE_HW_INTRINSICS
#if defined(TARGET_ARM64)
        CORINFO_CLASS_HANDLE Vector64FloatHandle;
        CORINFO_CLASS_HANDLE Vector64DoubleHandle;
        CORINFO_CLASS_HANDLE Vector64IntHandle;
        CORINFO_CLASS_HANDLE Vector64UShortHandle;
        CORINFO_CLASS_HANDLE Vector64UByteHandle;
        CORINFO_CLASS_HANDLE Vector64ShortHandle;
        CORINFO_CLASS_HANDLE Vector64ByteHandle;
        CORINFO_CLASS_HANDLE Vector64LongHandle;
        CORINFO_CLASS_HANDLE Vector64UIntHandle;
        CORINFO_CLASS_HANDLE Vector64ULongHandle;
        CORINFO_CLASS_HANDLE Vector64NIntHandle;
        CORINFO_CLASS_HANDLE Vector64NUIntHandle;
#endif // defined(TARGET_ARM64)
        CORINFO_CLASS_HANDLE Vector128FloatHandle;
        CORINFO_CLASS_HANDLE Vector128DoubleHandle;
        CORINFO_CLASS_HANDLE Vector128IntHandle;
        CORINFO_CLASS_HANDLE Vector128UShortHandle;
        CORINFO_CLASS_HANDLE Vector128UByteHandle;
        CORINFO_CLASS_HANDLE Vector128ShortHandle;
        CORINFO_CLASS_HANDLE Vector128ByteHandle;
        CORINFO_CLASS_HANDLE Vector128LongHandle;
        CORINFO_CLASS_HANDLE Vector128UIntHandle;
        CORINFO_CLASS_HANDLE Vector128ULongHandle;
        CORINFO_CLASS_HANDLE Vector128NIntHandle;
        CORINFO_CLASS_HANDLE Vector128NUIntHandle;
#if defined(TARGET_XARCH)
        CORINFO_CLASS_HANDLE Vector256FloatHandle;
        CORINFO_CLASS_HANDLE Vector256DoubleHandle;
        CORINFO_CLASS_HANDLE Vector256IntHandle;
        CORINFO_CLASS_HANDLE Vector256UShortHandle;
        CORINFO_CLASS_HANDLE Vector256UByteHandle;
        CORINFO_CLASS_HANDLE Vector256ShortHandle;
        CORINFO_CLASS_HANDLE Vector256ByteHandle;
        CORINFO_CLASS_HANDLE Vector256LongHandle;
        CORINFO_CLASS_HANDLE Vector256UIntHandle;
        CORINFO_CLASS_HANDLE Vector256ULongHandle;
        CORINFO_CLASS_HANDLE Vector256NIntHandle;
        CORINFO_CLASS_HANDLE Vector256NUIntHandle;
#endif // defined(TARGET_XARCH)
#endif // FEATURE_HW_INTRINSICS

        CORINFO_CLASS_HANDLE CanonicalSimd8Handle;
        CORINFO_CLASS_HANDLE CanonicalSimd16Handle;
        CORINFO_CLASS_HANDLE CanonicalSimd32Handle;

        SIMDHandlesCache()
        {
            memset(this, 0, sizeof(*this));
        }
    };

    SIMDHandlesCache* m_simdHandleCache;

    // Get the handle for a SIMD type.
    CORINFO_CLASS_HANDLE gtGetStructHandleForSIMD(var_types simdType, CorInfoType simdBaseJitType)
    {
        if (m_simdHandleCache == nullptr)
        {
            // This may happen if the JIT generates SIMD node on its own, without importing them.
            // Otherwise getBaseJitTypeAndSizeOfSIMDType should have created the cache.
            return NO_CLASS_HANDLE;
        }

        if (simdBaseJitType == CORINFO_TYPE_FLOAT)
        {
            switch (simdType)
            {
                case TYP_SIMD8:
                    return m_simdHandleCache->SIMDVector2Handle;
                case TYP_SIMD12:
                    return m_simdHandleCache->SIMDVector3Handle;
                case TYP_SIMD16:
                    if ((getSIMDVectorType() == TYP_SIMD32) ||
                        (m_simdHandleCache->SIMDVector4Handle != NO_CLASS_HANDLE))
                    {
                        return m_simdHandleCache->SIMDVector4Handle;
                    }
                    break;
                case TYP_SIMD32:
                    break;
                default:
                    unreached();
            }
        }
        assert(emitTypeSize(simdType) <= largestEnregisterableStructSize());
        switch (simdBaseJitType)
        {
            case CORINFO_TYPE_FLOAT:
                return m_simdHandleCache->SIMDFloatHandle;
            case CORINFO_TYPE_DOUBLE:
                return m_simdHandleCache->SIMDDoubleHandle;
            case CORINFO_TYPE_INT:
                return m_simdHandleCache->SIMDIntHandle;
            case CORINFO_TYPE_USHORT:
                return m_simdHandleCache->SIMDUShortHandle;
            case CORINFO_TYPE_UBYTE:
                return m_simdHandleCache->SIMDUByteHandle;
            case CORINFO_TYPE_SHORT:
                return m_simdHandleCache->SIMDShortHandle;
            case CORINFO_TYPE_BYTE:
                return m_simdHandleCache->SIMDByteHandle;
            case CORINFO_TYPE_LONG:
                return m_simdHandleCache->SIMDLongHandle;
            case CORINFO_TYPE_UINT:
                return m_simdHandleCache->SIMDUIntHandle;
            case CORINFO_TYPE_ULONG:
                return m_simdHandleCache->SIMDULongHandle;
            case CORINFO_TYPE_NATIVEINT:
                return m_simdHandleCache->SIMDNIntHandle;
            case CORINFO_TYPE_NATIVEUINT:
                return m_simdHandleCache->SIMDNUIntHandle;
            default:
                assert(!"Didn't find a class handle for simdType");
        }
        return NO_CLASS_HANDLE;
    }

#if defined(FEATURE_HW_INTRINSICS)
    CORINFO_CLASS_HANDLE gtGetStructHandleForSimdOrHW(var_types   simdType,
                                                      CorInfoType simdBaseJitType,
                                                      bool        isSimdAsHWIntrinsic = false)
    {
        CORINFO_CLASS_HANDLE clsHnd = NO_CLASS_HANDLE;

        if (isSimdAsHWIntrinsic)
        {
            clsHnd = gtGetStructHandleForSIMD(simdType, simdBaseJitType);
        }
        else
        {
            clsHnd = gtGetStructHandleForHWSIMD(simdType, simdBaseJitType);
        }

        return clsHnd;
    }
#endif // FEATURE_HW_INTRINSICS

    //------------------------------------------------------------------------
    // gtGetCanonicalStructHandleForSIMD: Get the "canonical" SIMD type handle.
    //
    // Some SIMD-typed trees do not carry struct handles with them (and in
    // some cases, they cannot, due to being created by the compiler itself).
    // To enable CSEing of these trees, we use "canonical" handles. These are
    // captured during importation, and can represent any type normalized to
    // be TYP_SIMD.
    //
    // Arguments:
    //    simdType - The SIMD type
    //
    // Return Value:
    //    The "canonical" type handle for "simdType", if one was available.
    //    "NO_CLASS_HANDLE" otherwise.
    //
    CORINFO_CLASS_HANDLE gtGetCanonicalStructHandleForSIMD(var_types simdType)
    {
        if (m_simdHandleCache == nullptr)
        {
            return NO_CLASS_HANDLE;
        }

        switch (simdType)
        {
            case TYP_SIMD8:
                return m_simdHandleCache->CanonicalSimd8Handle;
            case TYP_SIMD12:
                return m_simdHandleCache->SIMDVector3Handle;
            case TYP_SIMD16:
                return m_simdHandleCache->CanonicalSimd16Handle;
            case TYP_SIMD32:
                return m_simdHandleCache->CanonicalSimd32Handle;
            default:
                unreached();
        }
    }

    // Returns true if this is a SIMD type that should be considered an opaque
    // vector type (i.e. do not analyze or promote its fields).
    // Note that all but the fixed vector types are opaque, even though they may
    // actually be declared as having fields.
    bool isOpaqueSIMDType(CORINFO_CLASS_HANDLE structHandle) const
    {
        return ((m_simdHandleCache != nullptr) && (structHandle != m_simdHandleCache->SIMDVector2Handle) &&
                (structHandle != m_simdHandleCache->SIMDVector3Handle) &&
                (structHandle != m_simdHandleCache->SIMDVector4Handle));
    }

    // Returns true if the tree corresponds to a TYP_SIMD lcl var.
    // Note that both SIMD vector args and locals are mared as lvSIMDType = true, but
    // type of an arg node is TYP_BYREF and a local node is TYP_SIMD or TYP_STRUCT.
    bool isSIMDTypeLocal(GenTree* tree)
    {
        return tree->OperIsLocal() && lvaGetDesc(tree->AsLclVarCommon())->lvSIMDType;
    }

    // Returns true if the lclVar is an opaque SIMD type.
    bool isOpaqueSIMDLclVar(const LclVarDsc* varDsc) const
    {
        if (!varDsc->lvSIMDType)
        {
            return false;
        }
        return isOpaqueSIMDType(varDsc->GetStructHnd());
    }

    static bool isRelOpSIMDIntrinsic(SIMDIntrinsicID intrinsicId)
    {
        return (intrinsicId == SIMDIntrinsicEqual);
    }

    bool isNumericsNamespace(const char* ns)
    {
        return strcmp(ns, "System.Numerics") == 0;
    }

    bool isSIMDClass(CORINFO_CLASS_HANDLE clsHnd)
    {
        if (isIntrinsicType(clsHnd))
        {
            const char* namespaceName = nullptr;
            (void)getClassNameFromMetadata(clsHnd, &namespaceName);
            return isNumericsNamespace(namespaceName);
        }
        return false;
    }

    bool isSIMDClass(typeInfo* pTypeInfo)
    {
        return pTypeInfo->IsStruct() && isSIMDClass(pTypeInfo->GetClassHandleForValueClass());
    }

    bool isHWSIMDClass(CORINFO_CLASS_HANDLE clsHnd)
    {
#ifdef FEATURE_HW_INTRINSICS
        if (isIntrinsicType(clsHnd))
        {
            const char* namespaceName = nullptr;
            (void)getClassNameFromMetadata(clsHnd, &namespaceName);
            return strcmp(namespaceName, "System.Runtime.Intrinsics") == 0;
        }
#endif // FEATURE_HW_INTRINSICS
        return false;
    }

    bool isHWSIMDClass(typeInfo* pTypeInfo)
    {
#ifdef FEATURE_HW_INTRINSICS
        return pTypeInfo->IsStruct() && isHWSIMDClass(pTypeInfo->GetClassHandleForValueClass());
#else
        return false;
#endif
    }

    bool isSIMDorHWSIMDClass(CORINFO_CLASS_HANDLE clsHnd)
    {
        return isSIMDClass(clsHnd) || isHWSIMDClass(clsHnd);
    }

    bool isSIMDorHWSIMDClass(typeInfo* pTypeInfo)
    {
        return isSIMDClass(pTypeInfo) || isHWSIMDClass(pTypeInfo);
    }

    // Get the base (element) type and size in bytes for a SIMD type. Returns CORINFO_TYPE_UNDEF
    // if it is not a SIMD type or is an unsupported base JIT type.
    CorInfoType getBaseJitTypeAndSizeOfSIMDType(CORINFO_CLASS_HANDLE typeHnd, unsigned* sizeBytes = nullptr);

    CorInfoType getBaseJitTypeOfSIMDType(CORINFO_CLASS_HANDLE typeHnd)
    {
        return getBaseJitTypeAndSizeOfSIMDType(typeHnd, nullptr);
    }

    // Get SIMD Intrinsic info given the method handle.
    // Also sets typeHnd, argCount, baseType and sizeBytes out params.
    const SIMDIntrinsicInfo* getSIMDIntrinsicInfo(CORINFO_CLASS_HANDLE* typeHnd,
                                                  CORINFO_METHOD_HANDLE methodHnd,
                                                  CORINFO_SIG_INFO*     sig,
                                                  bool                  isNewObj,
                                                  unsigned*             argCount,
                                                  CorInfoType*          simdBaseJitType,
                                                  unsigned*             sizeBytes);

    // Pops and returns GenTree node from importers type stack.
    // Normalizes TYP_STRUCT value in case of GT_CALL, GT_RET_EXPR and arg nodes.
    GenTree* impSIMDPopStack(var_types type, bool expectAddr = false, CORINFO_CLASS_HANDLE structType = nullptr);

    // Transforms operands and returns the SIMD intrinsic to be applied on
    // transformed operands to obtain given relop result.
    SIMDIntrinsicID impSIMDRelOp(SIMDIntrinsicID      relOpIntrinsicId,
                                 CORINFO_CLASS_HANDLE typeHnd,
                                 unsigned             simdVectorSize,
                                 CorInfoType*         inOutBaseJitType,
                                 GenTree**            op1,
                                 GenTree**            op2);

#if defined(TARGET_XARCH)

    // Transforms operands and returns the SIMD intrinsic to be applied on
    // transformed operands to obtain == comparison result.
    SIMDIntrinsicID impSIMDLongRelOpEqual(CORINFO_CLASS_HANDLE typeHnd,
                                          unsigned             simdVectorSize,
                                          GenTree**            op1,
                                          GenTree**            op2);

#endif // defined(TARGET_XARCH)

    void setLclRelatedToSIMDIntrinsic(GenTree* tree);
    bool areFieldsContiguous(GenTree* op1, GenTree* op2);
    bool areLocalFieldsContiguous(GenTreeLclFld* first, GenTreeLclFld* second);
    bool areArrayElementsContiguous(GenTree* op1, GenTree* op2);
    bool areArgumentsContiguous(GenTree* op1, GenTree* op2);
    GenTree* createAddressNodeForSIMDInit(GenTree* tree, unsigned simdSize);

    // check methodHnd to see if it is a SIMD method that is expanded as an intrinsic in the JIT.
    GenTree* impSIMDIntrinsic(OPCODE                opcode,
                              GenTree*              newobjThis,
                              CORINFO_CLASS_HANDLE  clsHnd,
                              CORINFO_METHOD_HANDLE method,
                              CORINFO_SIG_INFO*     sig,
                              unsigned              methodFlags,
                              int                   memberRef);

    GenTree* getOp1ForConstructor(OPCODE opcode, GenTree* newobjThis, CORINFO_CLASS_HANDLE clsHnd);

    // Whether SIMD vector occupies part of SIMD register.
    // SSE2: vector2f/3f are considered sub register SIMD types.
    // AVX: vector2f, 3f and 4f are all considered sub register SIMD types.
    bool isSubRegisterSIMDType(GenTreeSIMD* simdNode)
    {
        unsigned vectorRegisterByteLength;
#if defined(TARGET_XARCH)
        // Calling the getSIMDVectorRegisterByteLength api causes the size of Vector<T> to be recorded
        // with the AOT compiler, so that it cannot change from aot compilation time to runtime
        // This api does not require such fixing as it merely pertains to the size of the simd type
        // relative to the Vector<T> size as used at compile time. (So detecting a vector length of 16 here
        // does not preclude the code from being used on a machine with a larger vector length.)
        if (getSIMDSupportLevel() < SIMD_AVX2_Supported)
        {
            vectorRegisterByteLength = 16;
        }
        else
        {
            vectorRegisterByteLength = 32;
        }
#else
        vectorRegisterByteLength = getSIMDVectorRegisterByteLength();
#endif
        return (simdNode->GetSimdSize() < vectorRegisterByteLength);
    }

    // Get the type for the hardware SIMD vector.
    // This is the maximum SIMD type supported for this target.
    var_types getSIMDVectorType()
    {
#if defined(TARGET_XARCH)
        if (getSIMDSupportLevel() == SIMD_AVX2_Supported)
        {
            return TYP_SIMD32;
        }
        else
        {
            // Verify and record that AVX2 isn't supported
            compVerifyInstructionSetUnusable(InstructionSet_AVX2);
            assert(getSIMDSupportLevel() >= SIMD_SSE2_Supported);
            return TYP_SIMD16;
        }
#elif defined(TARGET_ARM64)
        return TYP_SIMD16;
#else
        assert(!"getSIMDVectorType() unimplemented on target arch");
        unreached();
#endif
    }

    // Get the size of the SIMD type in bytes
    int getSIMDTypeSizeInBytes(CORINFO_CLASS_HANDLE typeHnd)
    {
        unsigned sizeBytes = 0;
        (void)getBaseJitTypeAndSizeOfSIMDType(typeHnd, &sizeBytes);
        return sizeBytes;
    }

    // Get the number of elements of baseType of SIMD vector given by its size and baseType
    static int getSIMDVectorLength(unsigned simdSize, var_types baseType);

    // Get the number of elements of baseType of SIMD vector given by its type handle
    int getSIMDVectorLength(CORINFO_CLASS_HANDLE typeHnd);

    // Get preferred alignment of SIMD type.
    int getSIMDTypeAlignment(var_types simdType);

    // Get the number of bytes in a System.Numeric.Vector<T> for the current compilation.
    // Note - cannot be used for System.Runtime.Intrinsic
    unsigned getSIMDVectorRegisterByteLength()
    {
#if defined(TARGET_XARCH)
        if (getSIMDSupportLevel() == SIMD_AVX2_Supported)
        {
            return YMM_REGSIZE_BYTES;
        }
        else
        {
            // Verify and record that AVX2 isn't supported
            compVerifyInstructionSetUnusable(InstructionSet_AVX2);
            assert(getSIMDSupportLevel() >= SIMD_SSE2_Supported);
            return XMM_REGSIZE_BYTES;
        }
#elif defined(TARGET_ARM64)
        return FP_REGSIZE_BYTES;
#else
        assert(!"getSIMDVectorRegisterByteLength() unimplemented on target arch");
        unreached();
#endif
    }

    // The minimum and maximum possible number of bytes in a SIMD vector.

    // maxSIMDStructBytes
    // The minimum SIMD size supported by System.Numeric.Vectors or System.Runtime.Intrinsic
    // SSE:  16-byte Vector<T> and Vector128<T>
    // AVX:  32-byte Vector256<T> (Vector<T> is 16-byte)
    // AVX2: 32-byte Vector<T> and Vector256<T>
    unsigned int maxSIMDStructBytes()
    {
#if defined(FEATURE_HW_INTRINSICS) && defined(TARGET_XARCH)
        if (compOpportunisticallyDependsOn(InstructionSet_AVX))
        {
            return YMM_REGSIZE_BYTES;
        }
        else
        {
            // Verify and record that AVX2 isn't supported
            compVerifyInstructionSetUnusable(InstructionSet_AVX2);
            assert(getSIMDSupportLevel() >= SIMD_SSE2_Supported);
            return XMM_REGSIZE_BYTES;
        }
#else
        return getSIMDVectorRegisterByteLength();
#endif
    }

    unsigned int minSIMDStructBytes()
    {
        return emitTypeSize(TYP_SIMD8);
    }

public:
    // Returns the codegen type for a given SIMD size.
    static var_types getSIMDTypeForSize(unsigned size)
    {
        var_types simdType = TYP_UNDEF;
        if (size == 8)
        {
            simdType = TYP_SIMD8;
        }
        else if (size == 12)
        {
            simdType = TYP_SIMD12;
        }
        else if (size == 16)
        {
            simdType = TYP_SIMD16;
        }
        else if (size == 32)
        {
            simdType = TYP_SIMD32;
        }
        else
        {
            noway_assert(!"Unexpected size for SIMD type");
        }
        return simdType;
    }

private:
    unsigned getSIMDInitTempVarNum(var_types simdType);

#else  // !FEATURE_SIMD
    bool isOpaqueSIMDLclVar(LclVarDsc* varDsc)
    {
        return false;
    }
#endif // FEATURE_SIMD

public:
    //------------------------------------------------------------------------
    // largestEnregisterableStruct: The size in bytes of the largest struct that can be enregistered.
    //
    // Notes: It is not guaranteed that the struct of this size or smaller WILL be a
    //        candidate for enregistration.

    unsigned largestEnregisterableStructSize()
    {
#ifdef FEATURE_SIMD
#if defined(FEATURE_HW_INTRINSICS) && defined(TARGET_XARCH)
        if (opts.IsReadyToRun())
        {
            // Return constant instead of maxSIMDStructBytes, as maxSIMDStructBytes performs
            // checks that are effected by the current level of instruction set support would
            // otherwise cause the highest level of instruction set support to be reported to crossgen2.
            // and this api is only ever used as an optimization or assert, so no reporting should
            // ever happen.
            return YMM_REGSIZE_BYTES;
        }
#endif // defined(FEATURE_HW_INTRINSICS) && defined(TARGET_XARCH)
        unsigned vectorRegSize = maxSIMDStructBytes();
        assert(vectorRegSize >= TARGET_POINTER_SIZE);
        return vectorRegSize;
#else  // !FEATURE_SIMD
        return TARGET_POINTER_SIZE;
#endif // !FEATURE_SIMD
    }

    // Use to determine if a struct *might* be a SIMD type. As this function only takes a size, many
    // structs will fit the criteria.
    bool structSizeMightRepresentSIMDType(size_t structSize)
    {
#ifdef FEATURE_SIMD
        // Do not use maxSIMDStructBytes as that api in R2R on X86 and X64 may notify the JIT
        // about the size of a struct under the assumption that the struct size needs to be recorded.
        // By using largestEnregisterableStructSize here, the detail of whether or not Vector256<T> is
        // enregistered or not will not be messaged to the R2R compiler.
        return (structSize >= minSIMDStructBytes()) && (structSize <= largestEnregisterableStructSize());
#else
        return false;
#endif // FEATURE_SIMD
    }

#ifdef FEATURE_SIMD
    static bool vnEncodesResultTypeForSIMDIntrinsic(SIMDIntrinsicID intrinsicId);
#endif // !FEATURE_SIMD
#ifdef FEATURE_HW_INTRINSICS
    static bool vnEncodesResultTypeForHWIntrinsic(NamedIntrinsic hwIntrinsicID);
#endif // FEATURE_HW_INTRINSICS

private:
    // These routines need not be enclosed under FEATURE_SIMD since lvIsSIMDType()
    // is defined for both FEATURE_SIMD and !FEATURE_SIMD appropriately. The use
    // of this routines also avoids the need of #ifdef FEATURE_SIMD specific code.

    // Is this var is of type simd struct?
    bool lclVarIsSIMDType(unsigned varNum)
    {
        return lvaGetDesc(varNum)->lvIsSIMDType();
    }

    // Returns true if the TYP_SIMD locals on stack are aligned at their
    // preferred byte boundary specified by getSIMDTypeAlignment().
    //
    // As per the Intel manual, the preferred alignment for AVX vectors is
    // 32-bytes. It is not clear whether additional stack space used in
    // aligning stack is worth the benefit and for now will use 16-byte
    // alignment for AVX 256-bit vectors with unaligned load/stores to/from
    // memory. On x86, the stack frame is aligned to 4 bytes. We need to extend
    // existing support for double (8-byte) alignment to 16 or 32 byte
    // alignment for frames with local SIMD vars, if that is determined to be
    // profitable.
    //
    // On Amd64 and SysV, RSP+8 is aligned on entry to the function (before
    // prolog has run). This means that in RBP-based frames RBP will be 16-byte
    // aligned. For RSP-based frames these are only sometimes aligned, depending
    // on the frame size.
    //
    bool isSIMDTypeLocalAligned(unsigned varNum)
    {
#if defined(FEATURE_SIMD) && ALIGN_SIMD_TYPES
        if (lclVarIsSIMDType(varNum) && lvaTable[varNum].lvType != TYP_BYREF)
        {
            // TODO-Cleanup: Can't this use the lvExactSize on the varDsc?
            int alignment = getSIMDTypeAlignment(lvaTable[varNum].lvType);
            if (alignment <= STACK_ALIGN)
            {
                bool rbpBased;
                int  off = lvaFrameAddress(varNum, &rbpBased);
                // On SysV and Winx64 ABIs RSP+8 will be 16-byte aligned at the
                // first instruction of a function. If our frame is RBP based
                // then RBP will always be 16 bytes aligned, so we can simply
                // check the offset.
                if (rbpBased)
                {
                    return (off % alignment) == 0;
                }

                // For RSP-based frame the alignment of RSP depends on our
                // locals. rsp+8 is aligned on entry and we just subtract frame
                // size so it is not hard to compute. Note that the compiler
                // tries hard to make sure the frame size means RSP will be
                // 16-byte aligned, but for leaf functions without locals (i.e.
                // frameSize = 0) it will not be.
                int frameSize = codeGen->genTotalFrameSize();
                return ((8 - frameSize + off) % alignment) == 0;
            }
        }
#endif // FEATURE_SIMD

        return false;
    }

#ifdef DEBUG
    // Answer the question: Is a particular ISA supported?
    // Use this api when asking the question so that future
    // ISA questions can be asked correctly or when asserting
    // support/nonsupport for an instruction set
    bool compIsaSupportedDebugOnly(CORINFO_InstructionSet isa) const
    {
#if defined(TARGET_XARCH) || defined(TARGET_ARM64)
        return opts.compSupportsISA.HasInstructionSet(isa);
#else
        return false;
#endif
    }
#endif // DEBUG

    bool notifyInstructionSetUsage(CORINFO_InstructionSet isa, bool supported) const;

    // Answer the question: Is a particular ISA allowed to be used implicitly by optimizations?
    // The result of this api call will exactly match the target machine
    // on which the function is executed (except for CoreLib, where there are special rules)
    bool compExactlyDependsOn(CORINFO_InstructionSet isa) const
    {
#if defined(TARGET_XARCH) || defined(TARGET_ARM64)
        if ((opts.compSupportsISAReported.HasInstructionSet(isa)) == false)
        {
            if (notifyInstructionSetUsage(isa, (opts.compSupportsISA.HasInstructionSet(isa))))
                ((Compiler*)this)->opts.compSupportsISAExactly.AddInstructionSet(isa);
            ((Compiler*)this)->opts.compSupportsISAReported.AddInstructionSet(isa);
        }
        return (opts.compSupportsISAExactly.HasInstructionSet(isa));
#else
        return false;
#endif
    }

    // Ensure that code will not execute if an instruction set is usable. Call only
    // if the instruction set has previously reported as unusable, but the status
    // has not yet been recorded to the AOT compiler.
    void compVerifyInstructionSetUnusable(CORINFO_InstructionSet isa)
    {
        // use compExactlyDependsOn to capture are record the use of the ISA.
        bool isaUsable = compExactlyDependsOn(isa);
        // Assert that the is unusable. If true, this function should never be called.
        assert(!isaUsable);
    }

    // Answer the question: Is a particular ISA allowed to be used implicitly by optimizations?
    // The result of this api call will match the target machine if the result is true.
    // If the result is false, then the target machine may have support for the instruction.
    bool compOpportunisticallyDependsOn(CORINFO_InstructionSet isa) const
    {
        if (opts.compSupportsISA.HasInstructionSet(isa))
        {
            return compExactlyDependsOn(isa);
        }
        else
        {
            return false;
        }
    }

    // Answer the question: Is a particular ISA supported for explicit hardware intrinsics?
    bool compHWIntrinsicDependsOn(CORINFO_InstructionSet isa) const
    {
        // Report intent to use the ISA to the EE
        compExactlyDependsOn(isa);
        return opts.compSupportsISA.HasInstructionSet(isa);
    }

    bool canUseVexEncoding() const
    {
#ifdef TARGET_XARCH
        return compOpportunisticallyDependsOn(InstructionSet_AVX);
#else
        return false;
#endif
    }

    //------------------------------------------------------------------------
    // canUseEvexEncoding - Answer the question: Is Evex encoding supported on this target.
    //
    // Returns:
    //    `true` if Evex encoding is supported, `false` if not.
    //
    bool canUseEvexEncoding() const
    {
#ifdef TARGET_XARCH

#ifdef DEBUG
        if (JitConfig.JitForceEVEXEncoding())
        {
            return true;
        }
#endif // DEBUG

        return compOpportunisticallyDependsOn(InstructionSet_AVX512F);
#else
        return false;
#endif
    }

    //------------------------------------------------------------------------
    // DoJitStressEvexEncoding- Answer the question: Do we force EVEX encoding.
    //
    // Returns:
    //    `true` if user requests EVEX encoding and it's safe, `false` if not.
    //
    bool DoJitStressEvexEncoding() const
    {
#if defined(TARGET_XARCH) && defined(DEBUG)
        // Using JitStressEVEXEncoding flag will force instructions which would
        // otherwise use VEX encoding but can be EVEX encoded to use EVEX encoding
        // This requires AVX512VL support. JitForceEVEXEncoding forces this encoding, thus
        // causing failure if not running on compatible hardware.

        if (JitConfig.JitForceEVEXEncoding())
        {
            return true;
        }
        if (JitConfig.JitStressEvexEncoding() && compOpportunisticallyDependsOn(InstructionSet_AVX512F_VL))
        {
            return true;
        }
#endif // TARGET_XARCH && DEBUG

        return false;
    }

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX                           Compiler                                        XX
    XX                                                                           XX
    XX   Generic info about the compilation and the method being compiled.       XX
    XX   It is responsible for driving the other phases.                         XX
    XX   It is also responsible for all the memory management.                   XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */

public:
    Compiler* InlineeCompiler; // The Compiler instance for the inlinee

    InlineResult* compInlineResult; // The result of importing the inlinee method.

    bool compDoAggressiveInlining;     // If true, mark every method as CORINFO_FLG_FORCEINLINE
    bool compJmpOpUsed;                // Does the method do a JMP
    bool compLongUsed;                 // Does the method use TYP_LONG
    bool compFloatingPointUsed;        // Does the method use TYP_FLOAT or TYP_DOUBLE
    bool compTailCallUsed;             // Does the method do a tailcall
    bool compTailPrefixSeen;           // Does the method IL have tail. prefix
    bool compMayConvertTailCallToLoop; // Does the method have a recursive tail call that we may convert to a loop?
    bool compLocallocSeen;             // Does the method IL have localloc opcode
    bool compLocallocUsed;             // Does the method use localloc.
    bool compLocallocOptimized;        // Does the method have an optimized localloc
    bool compQmarkUsed;                // Does the method use GT_QMARK/GT_COLON
    bool compQmarkRationalized;        // Is it allowed to use a GT_QMARK/GT_COLON node.
    bool compHasBackwardJump;          // Does the method (or some inlinee) have a lexically backwards jump?
    bool compHasBackwardJumpInHandler; // Does the method have a lexically backwards jump in a handler?
    bool compSwitchedToOptimized;      // Codegen initially was Tier0 but jit switched to FullOpts
    bool compSwitchedToMinOpts;        // Codegen initially was Tier1/FullOpts but jit switched to MinOpts
    bool compSuppressedZeroInit;       // There are vars with lvSuppressedZeroInit set

// NOTE: These values are only reliable after
//       the importing is completely finished.

#ifdef DEBUG
    // State information - which phases have completed?
    // These are kept together for easy discoverability

    bool    bRangeAllowStress;
    bool    compCodeGenDone;
    int64_t compNumStatementLinksTraversed; // # of links traversed while doing debug checks
    bool    fgNormalizeEHDone;              // Has the flowgraph EH normalization phase been done?
    size_t  compSizeEstimate;               // The estimated size of the method as per `gtSetEvalOrder`.
    size_t  compCycleEstimate;              // The estimated cycle count of the method as per `gtSetEvalOrder`
#endif                                      // DEBUG

    bool fgLocalVarLivenessDone; // Note that this one is used outside of debug.
    bool fgLocalVarLivenessChanged;
    bool compLSRADone;
    bool compRationalIRForm;

    bool compUsesThrowHelper; // There is a call to a THROW_HELPER for the compiled method.

    bool compGeneratingProlog;
    bool compGeneratingEpilog;
    bool compNeedsGSSecurityCookie; // There is an unsafe buffer (or localloc) on the stack.
                                    // Insert cookie on frame and code to check the cookie, like VC++ -GS.
    bool compGSReorderStackLayout;  // There is an unsafe buffer on the stack, reorder locals and make local
    // copies of susceptible parameters to avoid buffer overrun attacks through locals/params
    bool getNeedsGSSecurityCookie() const
    {
        return compNeedsGSSecurityCookie;
    }
    void setNeedsGSSecurityCookie()
    {
        compNeedsGSSecurityCookie = true;
    }

    FrameLayoutState lvaDoneFrameLayout; // The highest frame layout state that we've completed. During
                                         // frame layout calculations, this is the level we are currently
                                         // computing.

    //---------------------------- JITing options -----------------------------

    enum codeOptimize
    {
        BLENDED_CODE,
        SMALL_CODE,
        FAST_CODE,

        COUNT_OPT_CODE
    };

    struct Options
    {
        JitFlags* jitFlags; // all flags passed from the EE

        // The instruction sets that the compiler is allowed to emit.
        CORINFO_InstructionSetFlags compSupportsISA;
        // The instruction sets that were reported to the VM as being used by the current method. Subset of
        // compSupportsISA.
        CORINFO_InstructionSetFlags compSupportsISAReported;
        // The instruction sets that the compiler is allowed to take advantage of implicitly during optimizations.
        // Subset of compSupportsISA.
        // The instruction sets available in compSupportsISA and not available in compSupportsISAExactly can be only
        // used via explicit hardware intrinsics.
        CORINFO_InstructionSetFlags compSupportsISAExactly;

        void setSupportedISAs(CORINFO_InstructionSetFlags isas)
        {
            compSupportsISA = isas;
        }

        unsigned compFlags; // method attributes
        unsigned instrCount;
        unsigned lvRefCount;

        codeOptimize compCodeOpt; // what type of code optimizations

        bool compUseCMOV;

// optimize maximally and/or favor speed over size?

#define DEFAULT_MIN_OPTS_CODE_SIZE 60000
#define DEFAULT_MIN_OPTS_INSTR_COUNT 20000
#define DEFAULT_MIN_OPTS_BB_COUNT 2000
#define DEFAULT_MIN_OPTS_LV_NUM_COUNT 2000
#define DEFAULT_MIN_OPTS_LV_REF_COUNT 8000

// Maximum number of locals before turning off the inlining
#define MAX_LV_NUM_COUNT_FOR_INLINING 512

        bool compMinOpts;
        bool compMinOptsIsSet;
#ifdef DEBUG
        mutable bool compMinOptsIsUsed;

        bool MinOpts() const
        {
            assert(compMinOptsIsSet);
            compMinOptsIsUsed = true;
            return compMinOpts;
        }
        bool IsMinOptsSet() const
        {
            return compMinOptsIsSet;
        }
#else  // !DEBUG
        bool MinOpts() const
        {
            return compMinOpts;
        }
        bool IsMinOptsSet() const
        {
            return compMinOptsIsSet;
        }
#endif // !DEBUG

        bool OptimizationDisabled() const
        {
            return MinOpts() || compDbgCode;
        }
        bool OptimizationEnabled() const
        {
            return !OptimizationDisabled();
        }

        void SetMinOpts(bool val)
        {
            assert(!compMinOptsIsUsed);
            assert(!compMinOptsIsSet || (compMinOpts == val));
            compMinOpts      = val;
            compMinOptsIsSet = true;
        }

        // true if the CLFLG_* for an optimization is set.
        bool OptEnabled(unsigned optFlag) const
        {
            return !!(compFlags & optFlag);
        }

#ifdef FEATURE_READYTORUN
        bool IsReadyToRun() const
        {
            return jitFlags->IsSet(JitFlags::JIT_FLAG_READYTORUN);
        }
#else
        bool IsReadyToRun() const
        {
            return false;
        }
#endif

        // Check if the compilation is control-flow guard enabled.
        bool IsCFGEnabled() const
        {
#if defined(TARGET_ARM64) || defined(TARGET_AMD64)
            // On these platforms we assume the register that the target is
            // passed in is preserved by the validator and take care to get the
            // target from the register for the call (even in debug mode).
            static_assert_no_msg((RBM_VALIDATE_INDIRECT_CALL_TRASH & (1 << REG_VALIDATE_INDIRECT_CALL_ADDR)) == 0);
            if (JitConfig.JitForceControlFlowGuard())
                return true;

            return jitFlags->IsSet(JitFlags::JIT_FLAG_ENABLE_CFG);
#else
            // The remaining platforms are not supported and would require some
            // work to support.
            //
            // ARM32:
            //   The ARM32 validator does not preserve any volatile registers
            //   which means we have to take special care to allocate and use a
            //   callee-saved register (reloading the target from memory is a
            //   security issue).
            //
            // x86:
            //   On x86 some VSD calls disassemble the call site and expect an
            //   indirect call which is fundamentally incompatible with CFG.
            //   This would require a different way to pass this information
            //   through.
            //
            return false;
#endif
        }

#ifdef FEATURE_ON_STACK_REPLACEMENT
        bool IsOSR() const
        {
            return jitFlags->IsSet(JitFlags::JIT_FLAG_OSR);
        }
#else
        bool IsOSR() const
        {
            return false;
        }
#endif

        bool IsInstrumented() const
        {
            return jitFlags->IsSet(JitFlags::JIT_FLAG_BBINSTR);
        }

        bool IsInstrumentedOptimized() const
        {
            return IsInstrumented() && jitFlags->IsSet(JitFlags::JIT_FLAG_TIER1);
        }

        // true if we should use the PINVOKE_{BEGIN,END} helpers instead of generating
        // PInvoke transitions inline. Normally used by R2R, but also used when generating a reverse pinvoke frame, as
        // the current logic for frame setup initializes and pushes
        // the InlinedCallFrame before performing the Reverse PInvoke transition, which is invalid (as frames cannot
        // safely be pushed/popped while the thread is in a preemptive state.).
        bool ShouldUsePInvokeHelpers()
        {
            return jitFlags->IsSet(JitFlags::JIT_FLAG_USE_PINVOKE_HELPERS) ||
                   jitFlags->IsSet(JitFlags::JIT_FLAG_REVERSE_PINVOKE);
        }

        // true if we should use insert the REVERSE_PINVOKE_{ENTER,EXIT} helpers in the method
        // prolog/epilog
        bool IsReversePInvoke()
        {
            return jitFlags->IsSet(JitFlags::JIT_FLAG_REVERSE_PINVOKE);
        }

        bool compScopeInfo; // Generate the LocalVar info ?
        bool compDbgCode;   // Generate debugger-friendly code?
        bool compDbgInfo;   // Gather debugging info?
        bool compDbgEnC;

#ifdef PROFILING_SUPPORTED
        bool compNoPInvokeInlineCB;
#else
        static const bool compNoPInvokeInlineCB;
#endif

#ifdef DEBUG
        bool compGcChecks; // Check arguments and return values to ensure they are sane
#endif

#if defined(DEBUG) && defined(TARGET_XARCH)

        bool compStackCheckOnRet; // Check stack pointer on return to ensure it is correct.

#endif // defined(DEBUG) && defined(TARGET_XARCH)

#if defined(DEBUG) && defined(TARGET_X86)

        bool compStackCheckOnCall; // Check stack pointer after call to ensure it is correct. Only for x86.

#endif // defined(DEBUG) && defined(TARGET_X86)

        bool compReloc; // Generate relocs for pointers in code, true for all ngen/prejit codegen

#ifdef DEBUG
#if defined(TARGET_XARCH)
        bool compEnablePCRelAddr; // Whether absolute addr be encoded as PC-rel offset by RyuJIT where possible
#endif
#endif // DEBUG

#ifdef UNIX_AMD64_ABI
        // This flag  is indicating if there is a need to align the frame.
        // On AMD64-Windows, if there are calls, 4 slots for the outgoing ars are allocated, except for
        // FastTailCall. This slots makes the frame size non-zero, so alignment logic will be called.
        // On AMD64-Unix, there are no such slots. There is a possibility to have calls in the method with frame size of
        // 0. The frame alignment logic won't kick in. This flags takes care of the AMD64-Unix case by remembering that
        // there are calls and making sure the frame alignment logic is executed.
        bool compNeedToAlignFrame;
#endif // UNIX_AMD64_ABI

        bool compProcedureSplitting; // Separate cold code from hot code

        bool genFPorder; // Preserve FP order (operations are non-commutative)
        bool genFPopt;   // Can we do frame-pointer-omission optimization?
        bool altJit;     // True if we are an altjit and are compiling this method

#ifdef OPT_CONFIG
        bool optRepeat; // Repeat optimizer phases k times
#endif

        bool disAsm;      // Display native code as it is generated
        bool dspDiffable; // Makes the Jit Dump 'diff-able' (currently uses same COMPlus_* flag as disDiffable)
        bool disDiffable; // Makes the Disassembly code 'diff-able'
#ifdef DEBUG
        bool compProcedureSplittingEH; // Separate cold code from hot code for functions with EH
        bool dspCode;                  // Display native code generated
        bool dspEHTable;               // Display the EH table reported to the VM
        bool dspDebugInfo;             // Display the Debug info reported to the VM
        bool dspInstrs;                // Display the IL instructions intermixed with the native code output
        bool dspLines;                 // Display source-code lines intermixed with native code output
        bool dmpHex;                   // Display raw bytes in hex of native code output
        bool varNames;                 // Display variables names in native code output
        bool disAsmSpilled;            // Display native code when any register spilling occurs
        bool disasmWithGC;             // Display GC info interleaved with disassembly.
        bool disAddr;                  // Display process address next to each instruction in disassembly code
        bool disAlignment;             // Display alignment boundaries in disassembly code
        bool disAsm2;                  // Display native code after it is generated using external disassembler
        bool dspOrder;                 // Display names of each of the methods that we ngen/jit
        bool dspUnwind;                // Display the unwind info output
        bool compLongAddress;          // Force using large pseudo instructions for long address
                                       // (IF_LARGEJMP/IF_LARGEADR/IF_LARGLDC)
        bool dspGCtbls;                // Display the GC tables
#endif

// Default numbers used to perform loop alignment. All the numbers are chosen
// based on experimenting with various benchmarks.

// Default minimum loop block weight required to enable loop alignment.
#define DEFAULT_ALIGN_LOOP_MIN_BLOCK_WEIGHT 4

// By default a loop will be aligned at 32B address boundary to get better
// performance as per architecture manuals.
#define DEFAULT_ALIGN_LOOP_BOUNDARY 0x20

// For non-adaptive loop alignment, by default, only align a loop whose size is
// at most 3 times the alignment block size. If the loop is bigger than that, it is most
// likely complicated enough that loop alignment will not impact performance.
#define DEFAULT_MAX_LOOPSIZE_FOR_ALIGN DEFAULT_ALIGN_LOOP_BOUNDARY * 3

// By default only single iteration loops will be unrolled
#define DEFAULT_UNROLL_LOOP_MAX_ITERATION_COUNT 1

#ifdef DEBUG
        // Loop alignment variables

        // If set, for non-adaptive alignment, ensure loop jmps are not on or cross alignment boundary.
        bool compJitAlignLoopForJcc;
#endif
        // For non-adaptive alignment, minimum loop size (in bytes) for which alignment will be done.
        unsigned short compJitAlignLoopMaxCodeSize;

        // Minimum weight needed for the first block of a loop to make it a candidate for alignment.
        unsigned short compJitAlignLoopMinBlockWeight;

        // For non-adaptive alignment, address boundary (power of 2) at which loop alignment should
        // be done. By default, 32B.
        unsigned short compJitAlignLoopBoundary;

        // Padding limit to align a loop.
        unsigned short compJitAlignPaddingLimit;

        // If set, perform adaptive loop alignment that limits number of padding based on loop size.
        bool compJitAlignLoopAdaptive;

        // If set, tries to hide alignment instructions behind unconditional jumps.
        bool compJitHideAlignBehindJmp;

        // If set, tracks the hidden return buffer for struct arg.
        bool compJitOptimizeStructHiddenBuffer;

        // Iteration limit to unroll a loop.
        unsigned short compJitUnrollLoopMaxIterationCount;

#ifdef LATE_DISASM
        bool doLateDisasm; // Run the late disassembler
#endif                     // LATE_DISASM

#if DUMP_GC_TABLES && !defined(DEBUG)
#pragma message("NOTE: this non-debug build has GC ptr table dumping always enabled!")
        static const bool dspGCtbls = true;
#endif

#ifdef PROFILING_SUPPORTED
        // Whether to emit Enter/Leave/TailCall hooks using a dummy stub (DummyProfilerELTStub()).
        // This option helps make the JIT behave as if it is running under a profiler.
        bool compJitELTHookEnabled;
#endif // PROFILING_SUPPORTED

#if FEATURE_TAILCALL_OPT
        // Whether opportunistic or implicit tail call optimization is enabled.
        bool compTailCallOpt;
        // Whether optimization of transforming a recursive tail call into a loop is enabled.
        bool compTailCallLoopOpt;
#endif

#if FEATURE_FASTTAILCALL
        // Whether fast tail calls are allowed.
        bool compFastTailCalls;
#endif // FEATURE_FASTTAILCALL

#if defined(TARGET_ARM64)
        // Decision about whether to save FP/LR registers with callee-saved registers (see
        // COMPlus_JitSaveFpLrWithCalleSavedRegisters).
        int compJitSaveFpLrWithCalleeSavedRegisters;
#endif // defined(TARGET_ARM64)

#ifdef CONFIGURABLE_ARM_ABI
        bool compUseSoftFP = false;
#else
#ifdef ARM_SOFTFP
        static const bool compUseSoftFP = true;
#else  // !ARM_SOFTFP
        static const bool compUseSoftFP = false;
#endif // ARM_SOFTFP
#endif // CONFIGURABLE_ARM_ABI

        // Use early multi-dimensional array operator expansion (expand after loop optimizations; before lowering).
        bool compJitEarlyExpandMDArrays;

        // Collect 64 bit counts for PGO data.
        bool compCollect64BitCounts;

    } opts;

    static bool                s_pAltJitExcludeAssembliesListInitialized;
    static AssemblyNamesList2* s_pAltJitExcludeAssembliesList;

#ifdef DEBUG
    static bool                s_pJitDisasmIncludeAssembliesListInitialized;
    static AssemblyNamesList2* s_pJitDisasmIncludeAssembliesList;

    static bool       s_pJitFunctionFileInitialized;
    static MethodSet* s_pJitMethodSet;

// silence warning of cast to greater size. It is easier to silence than construct code the compiler is happy with, and
// it is safe in this case
#pragma warning(push)
#pragma warning(disable : 4312)

    template <typename T>
    T dspPtr(T p)
    {
        return (p == ZERO) ? ZERO : (opts.dspDiffable ? T(0xD1FFAB1E) : p);
    }

    template <typename T>
    T dspOffset(T o)
    {
        return (o == ZERO) ? ZERO : (opts.dspDiffable ? T(0xD1FFAB1E) : o);
    }
#pragma warning(pop)
#else
#pragma warning(push)
#pragma warning(disable : 4312)
    template <typename T>
    T dspPtr(T p)
    {
        return p;
    }

    template <typename T>
    T dspOffset(T o)
    {
        return o;
    }
#pragma warning(pop)
#endif

#ifdef DEBUG

    static int dspTreeID(GenTree* tree)
    {
        return tree->gtTreeID;
    }

    static void printStmtID(Statement* stmt)
    {
        assert(stmt != nullptr);
        printf(FMT_STMT, stmt->GetID());
    }

    static void printTreeID(GenTree* tree)
    {
        if (tree == nullptr)
        {
            printf("[------]");
        }
        else
        {
            printf("[%06d]", dspTreeID(tree));
        }
    }

    const char* pgoSourceToString(ICorJitInfo::PgoSource p);
    const char* devirtualizationDetailToString(CORINFO_DEVIRTUALIZATION_DETAIL detail);

#endif // DEBUG

// clang-format off
#define STRESS_MODES                                                                            \
                                                                                                \
        STRESS_MODE(NONE)                                                                       \
                                                                                                \
        /* "Variations" stress areas which we try to mix up with each other. */                 \
        /* These should not be exhaustively used as they might */                               \
        /* hide/trivialize other areas */                                                       \
                                                                                                \
        STRESS_MODE(REGS)                                                                       \
        STRESS_MODE(DBL_ALN)                                                                    \
        STRESS_MODE(LCL_FLDS)                                                                   \
        STRESS_MODE(UNROLL_LOOPS)                                                               \
        STRESS_MODE(MAKE_CSE)                                                                   \
        STRESS_MODE(LEGACY_INLINE)                                                              \
        STRESS_MODE(CLONE_EXPR)                                                                 \
        STRESS_MODE(USE_CMOV)                                                                   \
        STRESS_MODE(FOLD)                                                                       \
        STRESS_MODE(MERGED_RETURNS)                                                             \
        STRESS_MODE(BB_PROFILE)                                                                 \
        STRESS_MODE(OPT_BOOLS_GC)                                                               \
        STRESS_MODE(REMORPH_TREES)                                                              \
        STRESS_MODE(64RSLT_MUL)                                                                 \
        STRESS_MODE(DO_WHILE_LOOPS)                                                             \
        STRESS_MODE(MIN_OPTS)                                                                   \
        STRESS_MODE(REVERSE_FLAG)     /* Will set GTF_REVERSE_OPS whenever we can */            \
        STRESS_MODE(TAILCALL)         /* Will make the call as a tailcall whenever legal */     \
        STRESS_MODE(CATCH_ARG)        /* Will spill catch arg */                                \
        STRESS_MODE(UNSAFE_BUFFER_CHECKS)                                                       \
        STRESS_MODE(NULL_OBJECT_CHECK)                                                          \
        STRESS_MODE(PINVOKE_RESTORE_ESP)                                                        \
        STRESS_MODE(RANDOM_INLINE)                                                              \
        STRESS_MODE(SWITCH_CMP_BR_EXPANSION)                                                    \
        STRESS_MODE(GENERIC_VARN)                                                               \
        STRESS_MODE(PROFILER_CALLBACKS) /* Will generate profiler hooks for ELT callbacks */    \
        STRESS_MODE(BYREF_PROMOTION) /* Change undoPromotion decisions for byrefs */            \
        STRESS_MODE(PROMOTE_FEWER_STRUCTS)/* Don't promote some structs that can be promoted */ \
        STRESS_MODE(VN_BUDGET)/* Randomize the VN budget */                                     \
        STRESS_MODE(SSA_INFO) /* Select lower thresholds for "complex" SSA num encoding */      \
                                                                                                \
        /* After COUNT_VARN, stress level 2 does all of these all the time */                   \
                                                                                                \
        STRESS_MODE(COUNT_VARN)                                                                 \
                                                                                                \
        /* "Check" stress areas that can be exhaustively used if we */                          \
        /*  dont care about performance at all */                                               \
                                                                                                \
        STRESS_MODE(FORCE_INLINE) /* Treat every method as AggressiveInlining */                \
        STRESS_MODE(CHK_FLOW_UPDATE)                                                            \
        STRESS_MODE(EMITTER)                                                                    \
        STRESS_MODE(CHK_REIMPORT)                                                               \
        STRESS_MODE(GENERIC_CHECK)                                                              \
        STRESS_MODE(IF_CONVERSION_COST)                                                         \
        STRESS_MODE(IF_CONVERSION_INNER_LOOPS)                                                  \
        STRESS_MODE(COUNT)

    enum                compStressArea
    {
#define STRESS_MODE(mode) STRESS_##mode,
        STRESS_MODES
#undef STRESS_MODE
    };
// clang-format on

#ifdef DEBUG
    static const LPCWSTR s_compStressModeNames[STRESS_COUNT + 1];
    BYTE                 compActiveStressModes[STRESS_COUNT];
#endif // DEBUG

#define MAX_STRESS_WEIGHT 100

    bool compStressCompile(compStressArea stressArea, unsigned weightPercentage);
    bool compStressCompileHelper(compStressArea stressArea, unsigned weightPercentage);

#ifdef DEBUG

    bool compInlineStress()
    {
        return compStressCompile(STRESS_LEGACY_INLINE, 50);
    }

    bool compRandomInlineStress()
    {
        return compStressCompile(STRESS_RANDOM_INLINE, 50);
    }

    bool compPromoteFewerStructs(unsigned lclNum);

#endif // DEBUG

    bool compTailCallStress()
    {
#ifdef DEBUG
        // Do not stress tailcalls in IL stubs as the runtime creates several IL
        // stubs to implement the tailcall mechanism, which would then
        // recursively create more IL stubs.
        return !opts.jitFlags->IsSet(JitFlags::JIT_FLAG_IL_STUB) &&
               (JitConfig.TailcallStress() != 0 || compStressCompile(STRESS_TAILCALL, 5));
#else
        return false;
#endif
    }

    const char* compGetTieringName(bool wantShortName = false) const;
    const char* compGetPgoSourceName() const;
    const char* compGetStressMessage() const;

    codeOptimize compCodeOpt() const
    {
#if 0
        // Switching between size & speed has measurable throughput impact
        // (3.5% on NGen CoreLib when measured). It used to be enabled for
        // DEBUG, but should generate identical code between CHK & RET builds,
        // so that's not acceptable.
        // TODO-Throughput: Figure out what to do about size vs. speed & throughput.
        //                  Investigate the cause of the throughput regression.

        return opts.compCodeOpt;
#else
        return BLENDED_CODE;
#endif
    }

    //--------------------- Info about the procedure --------------------------

    struct Info
    {
        COMP_HANDLE           compCompHnd;
        CORINFO_MODULE_HANDLE compScopeHnd;
        CORINFO_CLASS_HANDLE  compClassHnd;
        CORINFO_METHOD_HANDLE compMethodHnd;
        CORINFO_METHOD_INFO*  compMethodInfo;

        bool hasCircularClassConstraints;
        bool hasCircularMethodConstraints;

#if defined(DEBUG) || defined(LATE_DISASM) || DUMP_FLOWGRAPHS

        const char* compMethodName;
        const char* compClassName;
        const char* compFullName;
        double      compPerfScore;
        int         compMethodSuperPMIIndex; // useful when debugging under SuperPMI

#endif // defined(DEBUG) || defined(LATE_DISASM) || DUMP_FLOWGRAPHS

#if defined(DEBUG) || defined(INLINE_DATA)
        // Method hash is logically const, but computed
        // on first demand.
        mutable unsigned compMethodHashPrivate;
        unsigned         compMethodHash() const;
#endif // defined(DEBUG) || defined(INLINE_DATA)

#ifdef PSEUDORANDOM_NOP_INSERTION
        // things for pseudorandom nop insertion
        unsigned  compChecksum;
        CLRRandom compRNG;
#endif

        // The following holds the FLG_xxxx flags for the method we're compiling.
        unsigned compFlags;

        // The following holds the class attributes for the method we're compiling.
        unsigned compClassAttr;

        const BYTE*     compCode;
        IL_OFFSET       compILCodeSize;     // The IL code size
        IL_OFFSET       compILImportSize;   // Estimated amount of IL actually imported
        IL_OFFSET       compILEntry;        // The IL entry point (normally 0)
        PatchpointInfo* compPatchpointInfo; // Patchpoint data for OSR (normally nullptr)
        UNATIVE_OFFSET  compNativeCodeSize; // The native code size, after instructions are issued. This
        // is less than (compTotalHotCodeSize + compTotalColdCodeSize) only if:
        // (1) the code is not hot/cold split, and we issued less code than we expected, or
        // (2) the code is hot/cold split, and we issued less code than we expected
        // in the cold section (the hot section will always be padded out to compTotalHotCodeSize).

        bool compIsStatic : 1;           // Is the method static (no 'this' pointer)?
        bool compIsVarArgs : 1;          // Does the method have varargs parameters?
        bool compInitMem : 1;            // Is the CORINFO_OPT_INIT_LOCALS bit set in the method info options?
        bool compProfilerCallback : 1;   // JIT inserted a profiler Enter callback
        bool compPublishStubParam : 1;   // EAX captured in prolog will be available through an intrinsic
        bool compHasNextCallRetAddr : 1; // The NextCallReturnAddress intrinsic is used.

        var_types compRetType;       // Return type of the method as declared in IL (including SIMD normalization)
        var_types compRetNativeType; // Normalized return type as per target arch ABI
        unsigned  compILargsCount;   // Number of arguments (incl. implicit but not hidden)
        unsigned  compArgsCount;     // Number of arguments (incl. implicit and     hidden)

#if FEATURE_FASTTAILCALL
        unsigned compArgStackSize; // Incoming argument stack size in bytes
#endif                             // FEATURE_FASTTAILCALL

        unsigned compRetBuffArg; // position of hidden return param var (0, 1) (BAD_VAR_NUM means not present);
        int compTypeCtxtArg; // position of hidden param for type context for generic code (CORINFO_CALLCONV_PARAMTYPE)
        unsigned       compThisArg; // position of implicit this pointer param (not to be confused with lvaArg0Var)
        unsigned       compILlocalsCount; // Number of vars : args + locals (incl. implicit but not hidden)
        unsigned       compLocalsCount;   // Number of vars : args + locals (incl. implicit and     hidden)
        unsigned       compMaxStack;
        UNATIVE_OFFSET compTotalHotCodeSize;  // Total number of bytes of Hot Code in the method
        UNATIVE_OFFSET compTotalColdCodeSize; // Total number of bytes of Cold Code in the method

        unsigned compUnmanagedCallCountWithGCTransition; // count of unmanaged calls with GC transition.

        CorInfoCallConvExtension compCallConv; // The entry-point calling convention for this method.

        unsigned compLvFrameListRoot; // lclNum for the Frame root
        unsigned compXcptnsCount;     // Number of exception-handling clauses read in the method's IL.
                                      // You should generally use compHndBBtabCount instead: it is the
                                      // current number of EH clauses (after additions like synchronized
        // methods and funclets, and removals like unreachable code deletion).

        Target::ArgOrder compArgOrder;

        bool compMatchedVM; // true if the VM is "matched": either the JIT is a cross-compiler
                            // and the VM expects that, or the JIT is a "self-host" compiler
                            // (e.g., x86 hosted targeting x86) and the VM expects that.

        /*  The following holds IL scope information about local variables.
         */

        unsigned     compVarScopesCount;
        VarScopeDsc* compVarScopes;

        /* The following holds information about instr offsets for
         * which we need to report IP-mappings
         */

        IL_OFFSET*                   compStmtOffsets; // sorted
        unsigned                     compStmtOffsetsCount;
        ICorDebugInfo::BoundaryTypes compStmtOffsetsImplicit;

#define CPU_X86 0x0100 // The generic X86 CPU
#define CPU_X86_PENTIUM_4 0x0110

#define CPU_X64 0x0200       // The generic x64 CPU
#define CPU_AMD_X64 0x0210   // AMD x64 CPU
#define CPU_INTEL_X64 0x0240 // Intel x64 CPU

#define CPU_ARM 0x0300   // The generic ARM CPU
#define CPU_ARM64 0x0400 // The generic ARM64 CPU

#define CPU_LOONGARCH64 0x0800 // The generic LOONGARCH64 CPU

        unsigned genCPU; // What CPU are we running on

        // Number of class profile probes in this method
        unsigned compHandleHistogramProbeCount;

    } info;

    ReturnTypeDesc compRetTypeDesc; // ABI return type descriptor for the method

    //------------------------------------------------------------------------
    // compMethodHasRetVal: Does this method return some kind of value?
    //
    // Return Value:
    //    If this method returns a struct via a return buffer, whether that
    //    buffer's address needs to be returned, otherwise whether signature
    //    return type is not "TYP_VOID".
    //
    bool compMethodHasRetVal() const
    {
        return (info.compRetBuffArg != BAD_VAR_NUM) ? compMethodReturnsRetBufAddr() : (info.compRetType != TYP_VOID);
    }

    // Returns true if the method being compiled returns RetBuf addr as its return value
    bool compMethodReturnsRetBufAddr() const
    {
        // There are cases where implicit RetBuf argument should be explicitly returned in a register.
        // In such cases the return type is changed to TYP_BYREF and appropriate IR is generated.
        // These cases are:
        CLANG_FORMAT_COMMENT_ANCHOR;
#ifdef TARGET_AMD64
        // 1. on x64 Windows and Unix the address of RetBuf needs to be returned by
        //    methods with hidden RetBufArg in RAX. In such case GT_RETURN is of TYP_BYREF,
        //    returning the address of RetBuf.
        return (info.compRetBuffArg != BAD_VAR_NUM);
#else // TARGET_AMD64
#ifdef PROFILING_SUPPORTED
        // 2.  Profiler Leave callback expects the address of retbuf as return value for
        //    methods with hidden RetBuf argument.  impReturnInstruction() when profiler
        //    callbacks are needed creates GT_RETURN(TYP_BYREF, op1 = Addr of RetBuf) for
        //    methods with hidden RetBufArg.
        if (compIsProfilerHookNeeded())
        {
            return (info.compRetBuffArg != BAD_VAR_NUM);
        }
#endif
        // 3. Windows ARM64 native instance calling convention requires the address of RetBuff
        //    to be returned in x0.
        CLANG_FORMAT_COMMENT_ANCHOR;
#if defined(TARGET_ARM64)
        if (TargetOS::IsWindows)
        {
            auto callConv = info.compCallConv;
            if (callConvIsInstanceMethodCallConv(callConv))
            {
                return (info.compRetBuffArg != BAD_VAR_NUM);
            }
        }
#endif // TARGET_ARM64
        // 4. x86 unmanaged calling conventions require the address of RetBuff to be returned in eax.
        CLANG_FORMAT_COMMENT_ANCHOR;
#if defined(TARGET_X86)
        if (info.compCallConv != CorInfoCallConvExtension::Managed)
        {
            return (info.compRetBuffArg != BAD_VAR_NUM);
        }
#endif

        return false;
#endif // TARGET_AMD64
    }

    //------------------------------------------------------------------------
    // compMethodReturnsMultiRegRetType: Does this method return a multi-reg value?
    //
    // Return Value:
    //    If this method returns a value in multiple registers, "true", "false"
    //    otherwise.
    //
    bool compMethodReturnsMultiRegRetType() const
    {
        return compRetTypeDesc.IsMultiRegRetType();
    }

    bool compEnregLocals()
    {
        return ((opts.compFlags & CLFLG_REGVAR) != 0);
    }

    bool compEnregStructLocals()
    {
        return (JitConfig.JitEnregStructLocals() != 0);
    }

    bool compObjectStackAllocation()
    {
        return (JitConfig.JitObjectStackAllocation() != 0);
    }

    // Returns true if the method requires a PInvoke prolog and epilog
    bool compMethodRequiresPInvokeFrame()
    {
        return (info.compUnmanagedCallCountWithGCTransition > 0);
    }

    // Returns true if address-exposed user variables should be poisoned with a recognizable value
    bool compShouldPoisonFrame()
    {
#ifdef FEATURE_ON_STACK_REPLACEMENT
        if (opts.IsOSR())
            return false;
#endif
        return !info.compInitMem && opts.compDbgCode;
    }

    // Returns true if the jit supports having patchpoints in this method.
    // Optionally, get the reason why not.
    bool compCanHavePatchpoints(const char** reason = nullptr);

#if defined(DEBUG)

    void compDispLocalVars();

#endif // DEBUG

private:
    class ClassLayoutTable* m_classLayoutTable;

    class ClassLayoutTable* typCreateClassLayoutTable();
    class ClassLayoutTable* typGetClassLayoutTable();

public:
    // Get the layout having the specified layout number.
    ClassLayout* typGetLayoutByNum(unsigned layoutNum);
    // Get the layout number of the specified layout.
    unsigned typGetLayoutNum(ClassLayout* layout);
    // Get the layout having the specified size but no class handle.
    ClassLayout* typGetBlkLayout(unsigned blockSize);
    // Get the number of a layout having the specified size but no class handle.
    unsigned typGetBlkLayoutNum(unsigned blockSize);
    // Get the layout for the specified class handle.
    ClassLayout* typGetObjLayout(CORINFO_CLASS_HANDLE classHandle);
    // Get the number of a layout for the specified class handle.
    unsigned typGetObjLayoutNum(CORINFO_CLASS_HANDLE classHandle);

//-------------------------- Global Compiler Data ------------------------------------

#ifdef DEBUG
private:
    static LONG s_compMethodsCount; // to produce unique label names
#endif

public:
#ifdef DEBUG
    unsigned compGenTreeID;
    unsigned compStatementID;
    unsigned compBasicBlockID;
#endif
    LONG compMethodID;

    BasicBlock* compCurBB;   // the current basic block in process
    Statement*  compCurStmt; // the current statement in process
    GenTree*    compCurTree; // the current tree in process

    //  The following is used to create the 'method JIT info' block.
    size_t compInfoBlkSize;
    BYTE*  compInfoBlkAddr;

    EHblkDsc* compHndBBtab;           // array of EH data
    unsigned  compHndBBtabCount;      // element count of used elements in EH data array
    unsigned  compHndBBtabAllocCount; // element count of allocated elements in EH data array

#if defined(TARGET_X86)

    //-------------------------------------------------------------------------
    //  Tracking of region covered by the monitor in synchronized methods
    void* syncStartEmitCookie; // the emitter cookie for first instruction after the call to MON_ENTER
    void* syncEndEmitCookie;   // the emitter cookie for first instruction after the call to MON_EXIT

#endif // !TARGET_X86

    Phases      mostRecentlyActivePhase; // the most recently active phase
    PhaseChecks activePhaseChecks;       // the currently active phase checks
    PhaseDumps  activePhaseDumps;        // the currently active phase dumps

    //-------------------------------------------------------------------------
    //  The following keeps track of how many bytes of local frame space we've
    //  grabbed so far in the current function, and how many argument bytes we
    //  need to pop when we return.
    //

    unsigned compLclFrameSize; // secObject+lclBlk+locals+temps

    // Count of callee-saved regs we pushed in the prolog.
    // Does not include EBP for isFramePointerUsed() and double-aligned frames.
    // In case of Amd64 this doesn't include float regs saved on stack.
    unsigned compCalleeRegsPushed;

#if defined(TARGET_XARCH)
    // Mask of callee saved float regs on stack.
    regMaskTP compCalleeFPRegsSavedMask;
#endif
#ifdef TARGET_AMD64
// Quirk for VS debug-launch scenario to work:
// Bytes of padding between save-reg area and locals.
#define VSQUIRK_STACK_PAD (2 * REGSIZE_BYTES)
    unsigned compVSQuirkStackPaddingNeeded;
#endif

    unsigned compArgSize; // total size of arguments in bytes (including register args (lvIsRegArg))

#ifdef TARGET_ARM
    bool compHasSplitParam;
#endif

    unsigned compMapILargNum(unsigned ILargNum);      // map accounting for hidden args
    unsigned compMapILvarNum(unsigned ILvarNum);      // map accounting for hidden args
    unsigned compMap2ILvarNum(unsigned varNum) const; // map accounting for hidden args

#if defined(TARGET_ARM64)
    struct FrameInfo
    {
        // Frame type (1-5)
        int frameType;

        // Distance from established (method body) SP to base of callee save area
        int calleeSaveSpOffset;

        // Amount to subtract from SP before saving (prolog) OR
        // to add to SP after restoring (epilog) callee saves
        int calleeSaveSpDelta;

        // Distance from established SP to where caller's FP was saved
        int offsetSpToSavedFp;
    } compFrameInfo;
#endif

    //-------------------------------------------------------------------------

    static void compStartup();  // One-time initialization
    static void compShutdown(); // One-time finalization

    void compInit(ArenaAllocator*       pAlloc,
                  CORINFO_METHOD_HANDLE methodHnd,
                  COMP_HANDLE           compHnd,
                  CORINFO_METHOD_INFO*  methodInfo,
                  InlineInfo*           inlineInfo);
    void compDone();

    static void compDisplayStaticSizes(FILE* fout);

    //------------ Some utility functions --------------

    void* compGetHelperFtn(CorInfoHelpFunc ftnNum,         /* IN  */
                           void**          ppIndirection); /* OUT */

    // Several JIT/EE interface functions return a CorInfoType, and also return a
    // class handle as an out parameter if the type is a value class.  Returns the
    // size of the type these describe.
    unsigned compGetTypeSize(CorInfoType cit, CORINFO_CLASS_HANDLE clsHnd);

#ifdef DEBUG
    // Components used by the compiler may write unit test suites, and
    // have them run within this method.  They will be run only once per process, and only
    // in debug.  (Perhaps should be under the control of a COMPlus_ flag.)
    // These should fail by asserting.
    void compDoComponentUnitTestsOnce();
#endif // DEBUG

    int compCompile(CORINFO_MODULE_HANDLE classPtr,
                    void**                methodCodePtr,
                    uint32_t*             methodCodeSize,
                    JitFlags*             compileFlags);
    void compCompileFinish();
    int compCompileHelper(CORINFO_MODULE_HANDLE classPtr,
                          COMP_HANDLE           compHnd,
                          CORINFO_METHOD_INFO*  methodInfo,
                          void**                methodCodePtr,
                          uint32_t*             methodCodeSize,
                          JitFlags*             compileFlag);

    ArenaAllocator* compGetArenaAllocator();

    void generatePatchpointInfo();

#if MEASURE_MEM_ALLOC
    static bool s_dspMemStats; // Display per-phase memory statistics for every function
#endif                         // MEASURE_MEM_ALLOC

#if LOOP_HOIST_STATS
    unsigned m_loopsConsidered;
    bool     m_curLoopHasHoistedExpression;
    unsigned m_loopsWithHoistedExpressions;
    unsigned m_totalHoistedExpressions;

    void AddLoopHoistStats();
    void PrintPerMethodLoopHoistStats();

    static CritSecObject s_loopHoistStatsLock; // This lock protects the data structures below.
    static unsigned      s_loopsConsidered;
    static unsigned      s_loopsWithHoistedExpressions;
    static unsigned      s_totalHoistedExpressions;

    static void PrintAggregateLoopHoistStats(FILE* f);
#endif // LOOP_HOIST_STATS

#if TRACK_ENREG_STATS
    class EnregisterStats
    {
    private:
        unsigned m_totalNumberOfVars;
        unsigned m_totalNumberOfStructVars;
        unsigned m_totalNumberOfEnregVars;
        unsigned m_totalNumberOfStructEnregVars;

        unsigned m_addrExposed;
        unsigned m_hiddenStructArg;
        unsigned m_VMNeedsStackAddr;
        unsigned m_localField;
        unsigned m_blockOp;
        unsigned m_dontEnregStructs;
        unsigned m_notRegSizeStruct;
        unsigned m_structArg;
        unsigned m_lclAddrNode;
        unsigned m_castTakesAddr;
        unsigned m_storeBlkSrc;
        unsigned m_oneAsgRetyping;
        unsigned m_swizzleArg;
        unsigned m_blockOpRet;
        unsigned m_returnSpCheck;
        unsigned m_callSpCheck;
        unsigned m_simdUserForcesDep;
        unsigned m_liveInOutHndlr;
        unsigned m_depField;
        unsigned m_noRegVars;
        unsigned m_minOptsGC;
#ifdef JIT32_GCENCODER
        unsigned m_PinningRef;
#endif // JIT32_GCENCODER
#if !defined(TARGET_64BIT)
        unsigned m_longParamField;
#endif // !TARGET_64BIT
        unsigned m_parentExposed;
        unsigned m_tooConservative;
        unsigned m_escapeAddress;
        unsigned m_osrExposed;
        unsigned m_stressLclFld;
        unsigned m_dispatchRetBuf;
        unsigned m_wideIndir;

    public:
        void RecordLocal(const LclVarDsc* varDsc);
        void Dump(FILE* fout) const;
    };

    static EnregisterStats s_enregisterStats;
#endif // TRACK_ENREG_STATS

    bool compIsForImportOnly();
    bool compIsForInlining() const;
    bool compDonotInline();

#ifdef DEBUG
    // Get the default fill char value we randomize this value when JitStress is enabled.
    static unsigned char compGetJitDefaultFill(Compiler* comp);

    const char* compLocalVarName(unsigned varNum, unsigned offs);
    VarName compVarName(regNumber reg, bool isFloatReg = false);
    const char* compFPregVarName(unsigned fpReg, bool displayVar = false);
    void compDspSrcLinesByNativeIP(UNATIVE_OFFSET curIP);
    void compDspSrcLinesByLineNum(unsigned line, bool seek = false);
#endif // DEBUG
    const char* compRegNameForSize(regNumber reg, size_t size);
    const char* compRegVarName(regNumber reg, bool displayVar = false, bool isFloatReg = false);

    //-------------------------------------------------------------------------

    struct VarScopeListNode
    {
        VarScopeDsc*             data;
        VarScopeListNode*        next;
        static VarScopeListNode* Create(VarScopeDsc* value, CompAllocator alloc)
        {
            VarScopeListNode* node = new (alloc) VarScopeListNode;
            node->data             = value;
            node->next             = nullptr;
            return node;
        }
    };

    struct VarScopeMapInfo
    {
        VarScopeListNode*       head;
        VarScopeListNode*       tail;
        static VarScopeMapInfo* Create(VarScopeListNode* node, CompAllocator alloc)
        {
            VarScopeMapInfo* info = new (alloc) VarScopeMapInfo;
            info->head            = node;
            info->tail            = node;
            return info;
        }
    };

    // Max value of scope count for which we would use linear search; for larger values we would use hashtable lookup.
    static const unsigned MAX_LINEAR_FIND_LCL_SCOPELIST = 32;

    typedef JitHashTable<unsigned, JitSmallPrimitiveKeyFuncs<unsigned>, VarScopeMapInfo*> VarNumToScopeDscMap;

    // Map to keep variables' scope indexed by varNum containing it's scope dscs at the index.
    VarNumToScopeDscMap* compVarScopeMap;

    VarScopeDsc* compFindLocalVar(unsigned varNum, unsigned lifeBeg, unsigned lifeEnd);

    VarScopeDsc* compFindLocalVar(unsigned varNum, unsigned offs);

    VarScopeDsc* compFindLocalVarLinear(unsigned varNum, unsigned offs);

    void compInitVarScopeMap();

    VarScopeDsc** compEnterScopeList; // List has the offsets where variables
                                      // enter scope, sorted by instr offset
    unsigned compNextEnterScope;

    VarScopeDsc** compExitScopeList; // List has the offsets where variables
                                     // go out of scope, sorted by instr offset
    unsigned compNextExitScope;

    void compInitScopeLists();

    void compResetScopeLists();

    VarScopeDsc* compGetNextEnterScope(unsigned offs, bool scan = false);

    VarScopeDsc* compGetNextExitScope(unsigned offs, bool scan = false);

    void compProcessScopesUntil(unsigned   offset,
                                VARSET_TP* inScope,
                                void (Compiler::*enterScopeFn)(VARSET_TP* inScope, VarScopeDsc*),
                                void (Compiler::*exitScopeFn)(VARSET_TP* inScope, VarScopeDsc*));

#ifdef DEBUG
    void compDispScopeLists();
#endif // DEBUG

    bool compIsProfilerHookNeeded() const;

    //-------------------------------------------------------------------------
    /*               Statistical Data Gathering                               */

    void compJitStats(); // call this function and enable
                         // various ifdef's below for statistical data

#if CALL_ARG_STATS
    void        compCallArgStats();
    static void compDispCallArgStats(FILE* fout);
#endif

    //-------------------------------------------------------------------------

protected:
#ifdef DEBUG
    bool skipMethod();
#endif

    ArenaAllocator* compArenaAllocator;

public:
    void compFunctionTraceStart();
    void compFunctionTraceEnd(void* methodCodePtr, ULONG methodCodeSize, bool isNYI);

protected:
    size_t compMaxUncheckedOffsetForNullObject;

    void compInitOptions(JitFlags* compileFlags);

    void compSetProcessor();
    void compInitDebuggingInfo();
    void compSetOptimizationLevel();
#if defined(TARGET_ARMARCH) || defined(TARGET_LOONGARCH64)
    bool compRsvdRegCheck(FrameLayoutState curState);
#endif
    void compCompile(void** methodCodePtr, uint32_t* methodCodeSize, JitFlags* compileFlags);

    // Clear annotations produced during optimizations; to be used between iterations when repeating opts.
    void ResetOptAnnotations();

    // Regenerate loop descriptors; to be used between iterations when repeating opts.
    void RecomputeLoopInfo();

#ifdef PROFILING_SUPPORTED
    // Data required for generating profiler Enter/Leave/TailCall hooks

    bool  compProfilerHookNeeded; // Whether profiler Enter/Leave/TailCall hook needs to be generated for the method
    void* compProfilerMethHnd;    // Profiler handle of the method being compiled. Passed as param to ELT callbacks
    bool  compProfilerMethHndIndirected; // Whether compProfilerHandle is pointer to the handle or is an actual handle
#endif

public:
    // Assumes called as part of process shutdown; does any compiler-specific work associated with that.
    static void ProcessShutdownWork(ICorStaticInfo* statInfo);

    CompAllocator getAllocator(CompMemKind cmk = CMK_Generic)
    {
        return CompAllocator(compArenaAllocator, cmk);
    }

    CompAllocator getAllocatorGC()
    {
        return getAllocator(CMK_GC);
    }

    CompAllocator getAllocatorLoopHoist()
    {
        return getAllocator(CMK_LoopHoist);
    }

#ifdef DEBUG
    CompAllocator getAllocatorDebugOnly()
    {
        return getAllocator(CMK_DebugOnly);
    }
#endif // DEBUG

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX                           IL verification stuff                           XX
    XX                                                                           XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */

public:
    EntryState verCurrentState;

    void verInitBBEntryState(BasicBlock* block, EntryState* currentState);

    void verInitCurrentState();
    void verResetCurrentState(BasicBlock* block, EntryState* currentState);

    void verConvertBBToThrowVerificationException(BasicBlock* block DEBUGARG(bool logMsg));
    void verHandleVerificationFailure(BasicBlock* block DEBUGARG(bool logMsg));
    typeInfo verMakeTypeInfoForLocal(unsigned lclNum);
    typeInfo verMakeTypeInfo(CORINFO_CLASS_HANDLE clsHnd); // converts from jit type representation to typeInfo
    typeInfo verMakeTypeInfo(CorInfoType          ciType,
                             CORINFO_CLASS_HANDLE clsHnd); // converts from jit type representation to typeInfo

    typeInfo verParseArgSigToTypeInfo(CORINFO_SIG_INFO* sig, CORINFO_ARG_LIST_HANDLE args);
    bool verIsByRefLike(const typeInfo& ti);

    void DECLSPEC_NORETURN verRaiseVerifyException(INDEBUG(const char* reason) DEBUGARG(const char* file)
                                                       DEBUGARG(unsigned line));
    void verRaiseVerifyExceptionIfNeeded(INDEBUG(const char* reason) DEBUGARG(const char* file)
                                             DEBUGARG(unsigned line));
    bool verCheckTailCallConstraint(OPCODE                  opcode,
                                    CORINFO_RESOLVED_TOKEN* pResolvedToken,
                                    CORINFO_RESOLVED_TOKEN* pConstrainedResolvedToken);

#ifdef DEBUG

    // One line log function. Default level is 0. Increasing it gives you
    // more log information

    // levels are currently unused: #define JITDUMP(level,...)                     ();
    void JitLogEE(unsigned level, const char* fmt, ...);

    bool compDebugBreak;

    bool compJitHaltMethod();

#endif

    /*
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XX                                                                           XX
    XX                   GS Security checks for unsafe buffers                   XX
    XX                                                                           XX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
    */
public:
    struct ShadowParamVarInfo
    {
        FixedBitVect* assignGroup; // the closure set of variables whose values depend on each other
        unsigned      shadowCopy;  // Lcl var num, if not valid set to BAD_VAR_NUM

        static bool mayNeedShadowCopy(LclVarDsc* varDsc)
        {
#if defined(TARGET_AMD64)
            // GS cookie logic to create shadow slots, create trees to copy reg args to shadow
            // slots and update all trees to refer to shadow slots is done immediately after
            // fgMorph().  Lsra could potentially mark a param as DoNotEnregister after JIT determines
            // not to shadow a parameter.  Also, LSRA could potentially spill a param which is passed
            // in register. Therefore, conservatively all params may need a shadow copy.  Note that
            // GS cookie logic further checks whether the param is a ptr or an unsafe buffer before
            // creating a shadow slot even though this routine returns true.
            //
            // TODO-AMD64-CQ: Revisit this conservative approach as it could create more shadow slots than
            // required. There are two cases under which a reg arg could potentially be used from its
            // home location:
            //   a) LSRA marks it as DoNotEnregister (see LinearScan::identifyCandidates())
            //   b) LSRA spills it
            //
            // Possible solution to address case (a)
            //   - The conditions under which LSRA marks a varDsc as DoNotEnregister could be checked
            //     in this routine.  Note that live out of exception handler is something we may not be
            //     able to do it here since GS cookie logic is invoked ahead of liveness computation.
            //     Therefore, for methods with exception handling and need GS cookie check we might have
            //     to take conservative approach.
            //
            // Possible solution to address case (b)
            //   - Whenever a parameter passed in an argument register needs to be spilled by LSRA, we
            //     create a new spill temp if the method needs GS cookie check.
            return varDsc->lvIsParam;
#else // !defined(TARGET_AMD64)
            return varDsc->lvIsParam && !varDsc->lvIsRegArg;
#endif
        }

#ifdef DEBUG
        void Print()
        {
            printf("assignGroup [%p]; shadowCopy: [%d];\n", assignGroup, shadowCopy);
        }
#endif
    };

    GSCookie*           gsGlobalSecurityCookieAddr; // Address of global cookie for unsafe buffer checks
    GSCookie            gsGlobalSecurityCookieVal;  // Value of global cookie if addr is NULL
    ShadowParamVarInfo* gsShadowVarInfo;            // Table used by shadow param analysis code

    PhaseStatus gsPhase();
    void        gsGSChecksInitCookie();   // Grabs cookie variable
    void        gsCopyShadowParams();     // Identify vulnerable params and create dhadow copies
    bool        gsFindVulnerableParams(); // Shadow param analysis code
    void        gsParamsToShadows();      // Insert copy code and replave param uses by shadow

    static fgWalkPreFn gsMarkPtrsAndAssignGroups; // Shadow param analysis tree-walk
    static fgWalkPreFn gsReplaceShadowParams;     // Shadow param replacement tree-walk

#define DEFAULT_MAX_INLINE_SIZE 100 // Methods with >  DEFAULT_MAX_INLINE_SIZE IL bytes will never be inlined.
                                    // This can be overwritten by setting complus_JITInlineSize env variable.

#define DEFAULT_MAX_INLINE_DEPTH 20 // Methods at more than this level deep will not be inlined

#define DEFAULT_MAX_LOCALLOC_TO_LOCAL_SIZE 32 // fixed locallocs of this size or smaller will convert to local buffers

private:
#ifdef FEATURE_JIT_METHOD_PERF
    JitTimer*                  pCompJitTimer;         // Timer data structure (by phases) for current compilation.
    static CompTimeSummaryInfo s_compJitTimerSummary; // Summary of the Timer information for the whole run.

    static LPCWSTR JitTimeLogCsv();        // Retrieve the file name for CSV from ConfigDWORD.
    static LPCWSTR compJitTimeLogFilename; // If a log file for JIT time is desired, filename to write it to.
#endif
    void BeginPhase(Phases phase); // Indicate the start of the given phase.
    void EndPhase(Phases phase);   // Indicate the end of the given phase.

#if MEASURE_CLRAPI_CALLS
    // Thin wrappers that call into JitTimer (if present).
    inline void CLRApiCallEnter(unsigned apix);
    inline void CLRApiCallLeave(unsigned apix);

public:
    inline void CLR_API_Enter(API_ICorJitInfo_Names ename);
    inline void CLR_API_Leave(API_ICorJitInfo_Names ename);

private:
#endif

#if defined(DEBUG) || defined(INLINE_DATA)
    // These variables are associated with maintaining SQM data about compile time.
    unsigned __int64 m_compCyclesAtEndOfInlining; // The thread-virtualized cycle count at the end of the inlining phase
                                                  // in the current compilation.
    unsigned __int64 m_compCycles;                // Net cycle count for current compilation
    DWORD m_compTickCountAtEndOfInlining; // The result of GetTickCount() (# ms since some epoch marker) at the end of
                                          // the inlining phase in the current compilation.
#endif                                    // defined(DEBUG) || defined(INLINE_DATA)

    // Records the SQM-relevant (cycles and tick count).  Should be called after inlining is complete.
    // (We do this after inlining because this marks the last point at which the JIT is likely to cause
    // type-loading and class initialization).
    void RecordStateAtEndOfInlining();
    // Assumes being called at the end of compilation.  Update the SQM state.
    void RecordStateAtEndOfCompilation();

public:
#if FUNC_INFO_LOGGING
    static LPCWSTR compJitFuncInfoFilename; // If a log file for per-function information is required, this is the
                                            // filename to write it to.
    static FILE* compJitFuncInfoFile;       // And this is the actual FILE* to write to.
#endif                                      // FUNC_INFO_LOGGING

    Compiler* prevCompiler; // Previous compiler on stack for TLS Compiler* linked list for reentrant compilers.

#if MEASURE_NOWAY
    void RecordNowayAssert(const char* filename, unsigned line, const char* condStr);
#endif // MEASURE_NOWAY

#ifndef FEATURE_TRACELOGGING
    // Should we actually fire the noway assert body and the exception handler?
    bool compShouldThrowOnNoway();
#else  // FEATURE_TRACELOGGING
    // Should we actually fire the noway assert body and the exception handler?
    bool compShouldThrowOnNoway(const char* filename, unsigned line);

    // Telemetry instance to use per method compilation.
    JitTelemetry compJitTelemetry;

    // Get common parameters that have to be logged with most telemetry data.
    void compGetTelemetryDefaults(const char** assemblyName,
                                  const char** scopeName,
                                  const char** methodName,
                                  unsigned*    methodHash);
#endif // !FEATURE_TRACELOGGING

#ifdef DEBUG
private:
    NodeToTestDataMap* m_nodeTestData;

    static const unsigned FIRST_LOOP_HOIST_CSE_CLASS = 1000;
    unsigned              m_loopHoistCSEClass; // LoopHoist test annotations turn into CSE requirements; we
                                               // label them with CSE Class #'s starting at FIRST_LOOP_HOIST_CSE_CLASS.
                                               // Current kept in this.
public:
    NodeToTestDataMap* GetNodeTestData()
    {
        Compiler* compRoot = impInlineRoot();
        if (compRoot->m_nodeTestData == nullptr)
        {
            compRoot->m_nodeTestData = new (getAllocatorDebugOnly()) NodeToTestDataMap(getAllocatorDebugOnly());
        }
        return compRoot->m_nodeTestData;
    }

    typedef JitHashTable<GenTree*, JitPtrKeyFuncs<GenTree>, int> NodeToIntMap;

    // Returns the set (i.e., the domain of the result map) of nodes that are keys in m_nodeTestData, and
    // currently occur in the AST graph.
    NodeToIntMap* FindReachableNodesInNodeTestData();

    // Node "from" is being eliminated, and being replaced by node "to".  If "from" had any associated
    // test data, associate that data with "to".
    void TransferTestDataToNode(GenTree* from, GenTree* to);

    // These are the methods that test that the various conditions implied by the
    // test attributes are satisfied.
    void JitTestCheckSSA(); // SSA builder tests.
    void JitTestCheckVN();  // Value numbering tests.
#endif                      // DEBUG

    FieldSeqStore* m_fieldSeqStore;

    FieldSeqStore* GetFieldSeqStore()
    {
        Compiler* compRoot = impInlineRoot();
        if (compRoot->m_fieldSeqStore == nullptr)
        {
            CompAllocator alloc       = getAllocator(CMK_FieldSeqStore);
            compRoot->m_fieldSeqStore = new (alloc) FieldSeqStore(alloc);
        }
        return compRoot->m_fieldSeqStore;
    }

    typedef JitHashTable<GenTree*, JitPtrKeyFuncs<GenTree>, unsigned> NodeToUnsignedMap;

    NodeToUnsignedMap* m_memorySsaMap[MemoryKindCount];

    // In some cases, we want to assign intermediate SSA #'s to memory states, and know what nodes create those memory
    // states. (We do this for try blocks, where, if the try block doesn't do a call that loses track of the memory
    // state, all the possible memory states are possible initial states of the corresponding catch block(s).)
    NodeToUnsignedMap* GetMemorySsaMap(MemoryKind memoryKind)
    {
        if (memoryKind == GcHeap && byrefStatesMatchGcHeapStates)
        {
            // Use the same map for GCHeap and ByrefExposed when their states match.
            memoryKind = ByrefExposed;
        }

        assert(memoryKind < MemoryKindCount);
        Compiler* compRoot = impInlineRoot();
        if (compRoot->m_memorySsaMap[memoryKind] == nullptr)
        {
            // Create a CompAllocator that labels sub-structure with CMK_MemorySsaMap, and use that for allocation.
            CompAllocator ialloc(getAllocator(CMK_MemorySsaMap));
            compRoot->m_memorySsaMap[memoryKind] = new (ialloc) NodeToUnsignedMap(ialloc);
        }
        return compRoot->m_memorySsaMap[memoryKind];
    }

    // The Refany type is the only struct type whose structure is implicitly assumed by IL.  We need its fields.
    CORINFO_CLASS_HANDLE m_refAnyClass;
    CORINFO_FIELD_HANDLE GetRefanyDataField()
    {
        if (m_refAnyClass == nullptr)
        {
            m_refAnyClass = info.compCompHnd->getBuiltinClass(CLASSID_TYPED_BYREF);
        }
        return info.compCompHnd->getFieldInClass(m_refAnyClass, 0);
    }
    CORINFO_FIELD_HANDLE GetRefanyTypeField()
    {
        if (m_refAnyClass == nullptr)
        {
            m_refAnyClass = info.compCompHnd->getBuiltinClass(CLASSID_TYPED_BYREF);
        }
        return info.compCompHnd->getFieldInClass(m_refAnyClass, 1);
    }

#if VARSET_COUNTOPS
    static BitSetSupport::BitSetOpCounter m_varsetOpCounter;
#endif
#if ALLVARSET_COUNTOPS
    static BitSetSupport::BitSetOpCounter m_allvarsetOpCounter;
#endif

    static HelperCallProperties s_helperCallProperties;

#ifdef UNIX_AMD64_ABI
    static var_types GetTypeFromClassificationAndSizes(SystemVClassificationType classType, int size);
    static var_types GetEightByteType(const SYSTEMV_AMD64_CORINFO_STRUCT_REG_PASSING_DESCRIPTOR& structDesc,
                                      unsigned                                                   slotNum);

    static void GetStructTypeOffset(const SYSTEMV_AMD64_CORINFO_STRUCT_REG_PASSING_DESCRIPTOR& structDesc,
                                    var_types*                                                 type0,
                                    var_types*                                                 type1,
                                    unsigned __int8*                                           offset0,
                                    unsigned __int8*                                           offset1);

    void GetStructTypeOffset(CORINFO_CLASS_HANDLE typeHnd,
                             var_types*           type0,
                             var_types*           type1,
                             unsigned __int8*     offset0,
                             unsigned __int8*     offset1);

#endif // defined(UNIX_AMD64_ABI)

    void fgMorphMultiregStructArgs(GenTreeCall* call);
    GenTree* fgMorphMultiregStructArg(CallArg* arg);

    bool killGCRefs(GenTree* tree);
}; // end of class Compiler

//---------------------------------------------------------------------------------------------------------------------
// GenTreeVisitor: a flexible tree walker implemented using the curiously-recurring-template pattern.
//
// This class implements a configurable walker for IR trees. There are five configuration options (defaults values are
// shown in parentheses):
//
// - ComputeStack (false): when true, the walker will push each node onto the `m_ancestors` stack. "Ancestors" is a bit
//                         of a misnomer, as the first entry will always be the current node.
//
// - DoPreOrder (false): when true, the walker will invoke `TVisitor::PreOrderVisit` with the current node as an
//                       argument before visiting the node's operands.
//
// - DoPostOrder (false): when true, the walker will invoke `TVisitor::PostOrderVisit` with the current node as an
//                        argument after visiting the node's operands.
//
// - DoLclVarsOnly (false): when true, the walker will only invoke `TVisitor::PreOrderVisit` for lclVar nodes.
//                          `DoPreOrder` must be true if this option is true.
//
// - UseExecutionOrder (false): when true, then walker will visit a node's operands in execution order (e.g. if a
//                              binary operator has the `GTF_REVERSE_OPS` flag set, the second operand will be
//                              visited before the first).
//
// At least one of `DoPreOrder` and `DoPostOrder` must be specified.
//
// A simple pre-order visitor might look something like the following:
//
//     class CountingVisitor final : public GenTreeVisitor<CountingVisitor>
//     {
//     public:
//         enum
//         {
//             DoPreOrder = true
//         };
//
//         unsigned m_count;
//
//         CountingVisitor(Compiler* compiler)
//             : GenTreeVisitor<CountingVisitor>(compiler), m_count(0)
//         {
//         }
//
//         Compiler::fgWalkResult PreOrderVisit(GenTree* node)
//         {
//             m_count++;
//         }
//     };
//
// This visitor would then be used like so:
//
//     CountingVisitor countingVisitor(compiler);
//     countingVisitor.WalkTree(root);
//
template <typename TVisitor>
class GenTreeVisitor
{
protected:
    typedef Compiler::fgWalkResult fgWalkResult;

    enum
    {
        ComputeStack      = false,
        DoPreOrder        = false,
        DoPostOrder       = false,
        DoLclVarsOnly     = false,
        UseExecutionOrder = false,
    };

    Compiler*            m_compiler;
    ArrayStack<GenTree*> m_ancestors;

    GenTreeVisitor(Compiler* compiler) : m_compiler(compiler), m_ancestors(compiler->getAllocator(CMK_ArrayStack))
    {
        assert(compiler != nullptr);

        static_assert_no_msg(TVisitor::DoPreOrder || TVisitor::DoPostOrder);
        static_assert_no_msg(!TVisitor::DoLclVarsOnly || TVisitor::DoPreOrder);
    }

    fgWalkResult PreOrderVisit(GenTree** use, GenTree* user)
    {
        return fgWalkResult::WALK_CONTINUE;
    }

    fgWalkResult PostOrderVisit(GenTree** use, GenTree* user)
    {
        return fgWalkResult::WALK_CONTINUE;
    }

public:
    fgWalkResult WalkTree(GenTree** use, GenTree* user)
    {
        assert(use != nullptr);

        GenTree* node = *use;

        if (TVisitor::ComputeStack)
        {
            m_ancestors.Push(node);
        }

        fgWalkResult result = fgWalkResult::WALK_CONTINUE;
        if (TVisitor::DoPreOrder && !TVisitor::DoLclVarsOnly)
        {
            result = reinterpret_cast<TVisitor*>(this)->PreOrderVisit(use, user);
            if (result == fgWalkResult::WALK_ABORT)
            {
                return result;
            }

            node = *use;
            if ((node == nullptr) || (result == fgWalkResult::WALK_SKIP_SUBTREES))
            {
                goto DONE;
            }
        }

        switch (node->OperGet())
        {
            // Leaf lclVars
            case GT_LCL_VAR:
            case GT_LCL_FLD:
            case GT_LCL_VAR_ADDR:
            case GT_LCL_FLD_ADDR:
                if (TVisitor::DoLclVarsOnly)
                {
                    result = reinterpret_cast<TVisitor*>(this)->PreOrderVisit(use, user);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }
                FALLTHROUGH;

            // Leaf nodes
            case GT_CATCH_ARG:
            case GT_LABEL:
            case GT_FTN_ADDR:
            case GT_RET_EXPR:
            case GT_CNS_INT:
            case GT_CNS_LNG:
            case GT_CNS_DBL:
            case GT_CNS_STR:
            case GT_CNS_VEC:
            case GT_MEMORYBARRIER:
            case GT_JMP:
            case GT_JCC:
            case GT_SETCC:
            case GT_NO_OP:
            case GT_START_NONGC:
            case GT_START_PREEMPTGC:
            case GT_PROF_HOOK:
#if !defined(FEATURE_EH_FUNCLETS)
            case GT_END_LFIN:
#endif // !FEATURE_EH_FUNCLETS
            case GT_PHI_ARG:
            case GT_JMPTABLE:
            case GT_CLS_VAR_ADDR:
            case GT_PHYSREG:
            case GT_EMITNOP:
            case GT_PINVOKE_PROLOG:
            case GT_PINVOKE_EPILOG:
            case GT_IL_OFFSET:
                break;

            // Lclvar unary operators
            case GT_STORE_LCL_VAR:
            case GT_STORE_LCL_FLD:
                if (TVisitor::DoLclVarsOnly)
                {
                    result = reinterpret_cast<TVisitor*>(this)->PreOrderVisit(use, user);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }
                FALLTHROUGH;

            // Standard unary operators
            case GT_NOT:
            case GT_NEG:
            case GT_BSWAP:
            case GT_BSWAP16:
            case GT_COPY:
            case GT_RELOAD:
            case GT_ARR_LENGTH:
            case GT_MDARR_LENGTH:
            case GT_MDARR_LOWER_BOUND:
            case GT_CAST:
            case GT_BITCAST:
            case GT_CKFINITE:
            case GT_LCLHEAP:
            case GT_ADDR:
            case GT_IND:
            case GT_OBJ:
            case GT_BLK:
            case GT_BOX:
            case GT_ALLOCOBJ:
            case GT_INIT_VAL:
            case GT_JTRUE:
            case GT_SWITCH:
            case GT_NULLCHECK:
            case GT_PUTARG_REG:
            case GT_PUTARG_STK:
            case GT_RETURNTRAP:
            case GT_NOP:
            case GT_FIELD:
            case GT_FIELD_ADDR:
            case GT_RETURN:
            case GT_RETFILT:
            case GT_RUNTIMELOOKUP:
            case GT_ARR_ADDR:
            case GT_KEEPALIVE:
            case GT_INC_SATURATE:
            {
                GenTreeUnOp* const unOp = node->AsUnOp();
                if (unOp->gtOp1 != nullptr)
                {
                    result = WalkTree(&unOp->gtOp1, unOp);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }
                break;
            }

            // Special nodes
            case GT_PHI:
                for (GenTreePhi::Use& use : node->AsPhi()->Uses())
                {
                    result = WalkTree(&use.NodeRef(), node);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }
                break;

            case GT_FIELD_LIST:
                for (GenTreeFieldList::Use& use : node->AsFieldList()->Uses())
                {
                    result = WalkTree(&use.NodeRef(), node);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }
                break;

            case GT_CMPXCHG:
            {
                GenTreeCmpXchg* const cmpXchg = node->AsCmpXchg();

                result = WalkTree(&cmpXchg->gtOpLocation, cmpXchg);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }
                result = WalkTree(&cmpXchg->gtOpValue, cmpXchg);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }
                result = WalkTree(&cmpXchg->gtOpComparand, cmpXchg);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }
                break;
            }

            case GT_ARR_ELEM:
            {
                GenTreeArrElem* const arrElem = node->AsArrElem();

                result = WalkTree(&arrElem->gtArrObj, arrElem);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }

                const unsigned rank = arrElem->gtArrRank;
                for (unsigned dim = 0; dim < rank; dim++)
                {
                    result = WalkTree(&arrElem->gtArrInds[dim], arrElem);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }
                break;
            }

            case GT_ARR_OFFSET:
            {
                GenTreeArrOffs* const arrOffs = node->AsArrOffs();

                result = WalkTree(&arrOffs->gtOffset, arrOffs);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }
                result = WalkTree(&arrOffs->gtIndex, arrOffs);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }
                result = WalkTree(&arrOffs->gtArrObj, arrOffs);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }
                break;
            }

            case GT_STORE_DYN_BLK:
            {
                GenTreeStoreDynBlk* const dynBlock = node->AsStoreDynBlk();

                GenTree** op1Use = &dynBlock->gtOp1;
                GenTree** op2Use = &dynBlock->gtOp2;
                GenTree** op3Use = &dynBlock->gtDynamicSize;

                result = WalkTree(op1Use, dynBlock);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }
                result = WalkTree(op2Use, dynBlock);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }
                result = WalkTree(op3Use, dynBlock);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }
                break;
            }

            case GT_CALL:
            {
                GenTreeCall* const call = node->AsCall();

                for (CallArg& arg : call->gtArgs.EarlyArgs())
                {
                    result = WalkTree(&arg.EarlyNodeRef(), call);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }

                for (CallArg& arg : call->gtArgs.LateArgs())
                {
                    result = WalkTree(&arg.LateNodeRef(), call);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }

                if (call->gtCallType == CT_INDIRECT)
                {
                    if (call->gtCallCookie != nullptr)
                    {
                        result = WalkTree(&call->gtCallCookie, call);
                        if (result == fgWalkResult::WALK_ABORT)
                        {
                            return result;
                        }
                    }

                    result = WalkTree(&call->gtCallAddr, call);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }

                if (call->gtControlExpr != nullptr)
                {
                    result = WalkTree(&call->gtControlExpr, call);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }

                break;
            }

#if defined(FEATURE_SIMD) || defined(FEATURE_HW_INTRINSICS)
#if defined(FEATURE_SIMD)
            case GT_SIMD:
#endif
#if defined(FEATURE_HW_INTRINSICS)
            case GT_HWINTRINSIC:
#endif
                if (TVisitor::UseExecutionOrder && node->IsReverseOp())
                {
                    assert(node->AsMultiOp()->GetOperandCount() == 2);

                    result = WalkTree(&node->AsMultiOp()->Op(2), node);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                    result = WalkTree(&node->AsMultiOp()->Op(1), node);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }
                else
                {
                    for (GenTree** use : node->AsMultiOp()->UseEdges())
                    {
                        result = WalkTree(use, node);
                        if (result == fgWalkResult::WALK_ABORT)
                        {
                            return result;
                        }
                    }
                }
                break;
#endif // defined(FEATURE_SIMD) || defined(FEATURE_HW_INTRINSICS)

            case GT_SELECT:
            {
                GenTreeConditional* const conditional = node->AsConditional();

                result = WalkTree(&conditional->gtCond, conditional);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }
                result = WalkTree(&conditional->gtOp1, conditional);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }
                result = WalkTree(&conditional->gtOp2, conditional);
                if (result == fgWalkResult::WALK_ABORT)
                {
                    return result;
                }
                break;
            }

            // Binary nodes
            default:
            {
                assert(node->OperIsBinary());

                GenTreeOp* const op = node->AsOp();

                GenTree** op1Use = &op->gtOp1;
                GenTree** op2Use = &op->gtOp2;

                if (TVisitor::UseExecutionOrder && node->IsReverseOp())
                {
                    std::swap(op1Use, op2Use);
                }

                if (*op1Use != nullptr)
                {
                    result = WalkTree(op1Use, op);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }

                if (*op2Use != nullptr)
                {
                    result = WalkTree(op2Use, op);
                    if (result == fgWalkResult::WALK_ABORT)
                    {
                        return result;
                    }
                }
                break;
            }
        }

    DONE:
        // Finally, visit the current node
        if (TVisitor::DoPostOrder)
        {
            result = reinterpret_cast<TVisitor*>(this)->PostOrderVisit(use, user);
        }

        if (TVisitor::ComputeStack)
        {
            m_ancestors.Pop();
        }

        return result;
    }
};

template <bool doPreOrder, bool doPostOrder, bool doLclVarsOnly, bool useExecutionOrder>
class GenericTreeWalker final
    : public GenTreeVisitor<GenericTreeWalker<doPreOrder, doPostOrder, doLclVarsOnly, useExecutionOrder>>
{
public:
    enum
    {
        ComputeStack      = false,
        DoPreOrder        = doPreOrder,
        DoPostOrder       = doPostOrder,
        DoLclVarsOnly     = doLclVarsOnly,
        UseExecutionOrder = useExecutionOrder,
    };

private:
    Compiler::fgWalkData* m_walkData;

public:
    GenericTreeWalker(Compiler::fgWalkData* walkData)
        : GenTreeVisitor<GenericTreeWalker<doPreOrder, doPostOrder, doLclVarsOnly, useExecutionOrder>>(
              walkData->compiler)
        , m_walkData(walkData)
    {
        assert(walkData != nullptr);
    }

    Compiler::fgWalkResult PreOrderVisit(GenTree** use, GenTree* user)
    {
        m_walkData->parent = user;
        return m_walkData->wtprVisitorFn(use, m_walkData);
    }

    Compiler::fgWalkResult PostOrderVisit(GenTree** use, GenTree* user)
    {
        m_walkData->parent = user;
        return m_walkData->wtpoVisitorFn(use, m_walkData);
    }
};

// A dominator tree visitor implemented using the curiously-recurring-template pattern, similar to GenTreeVisitor.
template <typename TVisitor>
class DomTreeVisitor
{
protected:
    Compiler* const    m_compiler;
    DomTreeNode* const m_domTree;

    DomTreeVisitor(Compiler* compiler, DomTreeNode* domTree) : m_compiler(compiler), m_domTree(domTree)
    {
    }

    void Begin()
    {
    }

    void PreOrderVisit(BasicBlock* block)
    {
    }

    void PostOrderVisit(BasicBlock* block)
    {
    }

    void End()
    {
    }

public:
    //------------------------------------------------------------------------
    // WalkTree: Walk the dominator tree, starting from fgFirstBB.
    //
    // Notes:
    //    This performs a non-recursive, non-allocating walk of the tree by using
    //    DomTreeNode's firstChild and nextSibling links to locate the children of
    //    a node and BasicBlock's bbIDom parent link to go back up the tree when
    //    no more children are left.
    //
    //    Forests are also supported, provided that all the roots are chained via
    //    DomTreeNode::nextSibling to fgFirstBB.
    //
    void WalkTree()
    {
        static_cast<TVisitor*>(this)->Begin();

        for (BasicBlock *next, *block = m_compiler->fgFirstBB; block != nullptr; block = next)
        {
            static_cast<TVisitor*>(this)->PreOrderVisit(block);

            next = m_domTree[block->bbNum].firstChild;

            if (next != nullptr)
            {
                assert(next->bbIDom == block);
                continue;
            }

            do
            {
                static_cast<TVisitor*>(this)->PostOrderVisit(block);

                next = m_domTree[block->bbNum].nextSibling;

                if (next != nullptr)
                {
                    assert(next->bbIDom == block->bbIDom);
                    break;
                }

                block = block->bbIDom;

            } while (block != nullptr);
        }

        static_cast<TVisitor*>(this)->End();
    }
};

// EHClauses: adapter class for forward iteration of the exception handling table using range-based `for`, e.g.:
//    for (EHblkDsc* const ehDsc : EHClauses(compiler))
//
class EHClauses
{
    EHblkDsc* m_begin;
    EHblkDsc* m_end;

    // Forward iterator for the exception handling table entries. Iteration is in table order.
    //
    class iterator
    {
        EHblkDsc* m_ehDsc;

    public:
        iterator(EHblkDsc* ehDsc) : m_ehDsc(ehDsc)
        {
        }

        EHblkDsc* operator*() const
        {
            return m_ehDsc;
        }

        iterator& operator++()
        {
            ++m_ehDsc;
            return *this;
        }

        bool operator!=(const iterator& i) const
        {
            return m_ehDsc != i.m_ehDsc;
        }
    };

public:
    EHClauses(Compiler* comp) : m_begin(comp->compHndBBtab), m_end(comp->compHndBBtab + comp->compHndBBtabCount)
    {
        assert((m_begin != nullptr) || (m_begin == m_end));
    }

    iterator begin() const
    {
        return iterator(m_begin);
    }

    iterator end() const
    {
        return iterator(m_end);
    }
};

/*
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XX                                                                           XX
XX                   Miscellaneous Compiler stuff                            XX
XX                                                                           XX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
*/

class StringPrinter
{
    CompAllocator m_alloc;
    char*         m_buffer;
    size_t        m_bufferMax;
    size_t        m_bufferIndex = 0;

    void Grow(size_t newSize);

public:
    StringPrinter(CompAllocator alloc, char* buffer = nullptr, size_t bufferMax = 0)
        : m_alloc(alloc), m_buffer(buffer), m_bufferMax(bufferMax)
    {
        if ((m_buffer == nullptr) || (m_bufferMax == 0))
        {
            m_bufferMax = 128;
            m_buffer    = alloc.allocate<char>(m_bufferMax);
        }

        m_buffer[0] = '\0';
    }

    size_t GetLength()
    {
        return m_bufferIndex;
    }

    char* GetBuffer()
    {
        assert(m_buffer[GetLength()] == '\0');
        return m_buffer;
    }
    void Truncate(size_t newLength)
    {
        assert(newLength <= m_bufferIndex);
        m_bufferIndex           = newLength;
        m_buffer[m_bufferIndex] = '\0';
    }

    void Append(const char* str);
    void Append(char chr);
};

/*****************************************************************************
 *
 *  Variables to keep track of total code amounts.
 */

#if DISPLAY_SIZES

extern size_t grossVMsize;
extern size_t grossNCsize;
extern size_t totalNCsize;

extern unsigned genMethodICnt;
extern unsigned genMethodNCnt;
extern size_t   gcHeaderISize;
extern size_t   gcPtrMapISize;
extern size_t   gcHeaderNSize;
extern size_t   gcPtrMapNSize;

#endif // DISPLAY_SIZES

/*****************************************************************************
 *
 *  Variables to keep track of basic block counts (more data on 1 BB methods)
 */

#if COUNT_BASIC_BLOCKS
extern Histogram bbCntTable;
extern Histogram bbOneBBSizeTable;
#endif

/*****************************************************************************
 *
 *  Used by optFindNaturalLoops to gather statistical information such as
 *   - total number of natural loops
 *   - number of loops with 1, 2, ... exit conditions
 *   - number of loops that have an iterator (for like)
 *   - number of loops that have a constant iterator
 */

#if COUNT_LOOPS

extern unsigned  totalLoopMethods;        // counts the total number of methods that have natural loops
extern unsigned  maxLoopsPerMethod;       // counts the maximum number of loops a method has
extern unsigned  totalLoopOverflows;      // # of methods that identified more loops than we can represent
extern unsigned  totalLoopCount;          // counts the total number of natural loops
extern unsigned  totalUnnatLoopCount;     // counts the total number of (not-necessarily natural) loops
extern unsigned  totalUnnatLoopOverflows; // # of methods that identified more unnatural loops than we can represent
extern unsigned  iterLoopCount;           // counts the # of loops with an iterator (for like)
extern unsigned  constIterLoopCount;      // counts the # of loops with a constant iterator (for like)
extern bool      hasMethodLoops;          // flag to keep track if we already counted a method as having loops
extern unsigned  loopsThisMethod;         // counts the number of loops in the current method
extern bool      loopOverflowThisMethod;  // True if we exceeded the max # of loops in the method.
extern Histogram loopCountTable;          // Histogram of loop counts
extern Histogram loopExitCountTable;      // Histogram of loop exit counts

#endif // COUNT_LOOPS

/*****************************************************************************
 * variables to keep track of how many iterations we go in a dataflow pass
 */

#if DATAFLOW_ITER

extern unsigned CSEiterCount; // counts the # of iteration for the CSE dataflow
extern unsigned CFiterCount;  // counts the # of iteration for the Const Folding dataflow

#endif // DATAFLOW_ITER

#if MEASURE_BLOCK_SIZE
extern size_t genFlowNodeSize;
extern size_t genFlowNodeCnt;
#endif // MEASURE_BLOCK_SIZE

#if MEASURE_NODE_SIZE
struct NodeSizeStats
{
    void Init()
    {
        genTreeNodeCnt        = 0;
        genTreeNodeSize       = 0;
        genTreeNodeActualSize = 0;
    }

    // Count of tree nodes allocated.
    unsigned __int64 genTreeNodeCnt;

    // The size we allocate.
    unsigned __int64 genTreeNodeSize;

    // The actual size of the node. Note that the actual size will likely be smaller
    // than the allocated size, but we sometimes use SetOper()/ChangeOper() to change
    // a smaller node to a larger one. TODO-Cleanup: add stats on
    // SetOper()/ChangeOper() usage to quantify this.
    unsigned __int64 genTreeNodeActualSize;
};
extern NodeSizeStats genNodeSizeStats;        // Total node size stats
extern NodeSizeStats genNodeSizeStatsPerFunc; // Per-function node size stats
extern Histogram     genTreeNcntHist;
extern Histogram     genTreeNsizHist;
#endif // MEASURE_NODE_SIZE

/*****************************************************************************
 *  Count fatal errors (including noway_asserts).
 */

#if MEASURE_FATAL
extern unsigned fatal_badCode;
extern unsigned fatal_noWay;
extern unsigned fatal_implLimitation;
extern unsigned fatal_NOMEM;
extern unsigned fatal_noWayAssertBody;
#ifdef DEBUG
extern unsigned fatal_noWayAssertBodyArgs;
#endif // DEBUG
extern unsigned fatal_NYI;
#endif // MEASURE_FATAL

/*****************************************************************************
 * Codegen
 */

#ifdef TARGET_XARCH

const instruction INS_SHIFT_LEFT_LOGICAL  = INS_shl;
const instruction INS_SHIFT_RIGHT_LOGICAL = INS_shr;
const instruction INS_SHIFT_RIGHT_ARITHM  = INS_sar;

const instruction INS_AND             = INS_and;
const instruction INS_OR              = INS_or;
const instruction INS_XOR             = INS_xor;
const instruction INS_NEG             = INS_neg;
const instruction INS_TEST            = INS_test;
const instruction INS_MUL             = INS_imul;
const instruction INS_SIGNED_DIVIDE   = INS_idiv;
const instruction INS_UNSIGNED_DIVIDE = INS_div;
const instruction INS_BREAKPOINT      = INS_int3;
const instruction INS_ADDC            = INS_adc;
const instruction INS_SUBC            = INS_sbb;
const instruction INS_NOT             = INS_not;

#endif // TARGET_XARCH

#ifdef TARGET_ARM

const instruction INS_SHIFT_LEFT_LOGICAL  = INS_lsl;
const instruction INS_SHIFT_RIGHT_LOGICAL = INS_lsr;
const instruction INS_SHIFT_RIGHT_ARITHM  = INS_asr;

const instruction INS_AND             = INS_and;
const instruction INS_OR              = INS_orr;
const instruction INS_XOR             = INS_eor;
const instruction INS_NEG             = INS_rsb;
const instruction INS_TEST            = INS_tst;
const instruction INS_MUL             = INS_mul;
const instruction INS_MULADD          = INS_mla;
const instruction INS_SIGNED_DIVIDE   = INS_sdiv;
const instruction INS_UNSIGNED_DIVIDE = INS_udiv;
const instruction INS_BREAKPOINT      = INS_bkpt;
const instruction INS_ADDC            = INS_adc;
const instruction INS_SUBC            = INS_sbc;
const instruction INS_NOT             = INS_mvn;

const instruction INS_ABS  = INS_vabs;
const instruction INS_SQRT = INS_vsqrt;

#endif // TARGET_ARM

#ifdef TARGET_ARM64

const instruction        INS_MULADD = INS_madd;
inline const instruction INS_BREAKPOINT_osHelper()
{
    // GDB needs the encoding of brk #0
    // Windbg needs the encoding of brk #F000
    return TargetOS::IsUnix ? INS_brk_unix : INS_brk_windows;
}
#define INS_BREAKPOINT INS_BREAKPOINT_osHelper()

const instruction INS_ABS  = INS_fabs;
const instruction INS_SQRT = INS_fsqrt;

#endif // TARGET_ARM64

#ifdef TARGET_LOONGARCH64
const instruction INS_BREAKPOINT = INS_break;
const instruction INS_MULADD     = INS_fmadd_d; // NOTE: default is double.
const instruction INS_ABS        = INS_fabs_d;  // NOTE: default is double.
const instruction INS_SQRT       = INS_fsqrt_d; // NOTE: default is double.
#endif                                          // TARGET_LOONGARCH64

/*****************************************************************************/

extern const BYTE genTypeSizes[];
extern const BYTE genTypeAlignments[];
extern const BYTE genTypeStSzs[];
extern const BYTE genActualTypes[];

/*****************************************************************************/

#ifdef DEBUG
void dumpConvertedVarSet(Compiler* comp, VARSET_VALARG_TP vars);
#endif // DEBUG

#include "compiler.hpp" // All the shared inline functions

/*****************************************************************************/
#endif //_COMPILER_H_
/*****************************************************************************/